diff --git a/src/components/Lesson.vue b/src/components/Lesson.vue
index ba6690242..b2986b5be 100644
--- a/src/components/Lesson.vue
+++ b/src/components/Lesson.vue
@@ -1,121 +1,124 @@
 <template>
   <div>
-    <header class="bg-navy pa2 pa3-ns flex items-center justify-around">
-      <a href='/#/' class="db-ns link flex-auto">
-        <img src="../images/ps_logo_horiz_white.svg" alt="ProtoSchool" style="height: 80px" class="ml3-ns"/>
-      </a>
-      <div class="tr dn db-ns">
-        <img src="../images/ipfs-illustrations-how-3.svg" alt="" style="height: 50px">
+    <Header/>
+    <div class="center mw7 ph2">
+      <div class="flex-l items-start  center mw7 ph2">
+        <section class="pv3 mt3">
+            <div class="lh-solid v-mid f4">
+              <span class="green v-mid"><span class="b">{{workshopShortname}}</span> | Lesson {{lessonNumber}} of {{lessonsInWorkshop}}</span>
+              <span class="pl1"><img v-if="lessonPassed" src="../images/complete.svg" alt="complete" style="height: 1.2rem;" class="v-mid"/></span>
+            </div>
+            <h1>{{lessonTitle}}</h1>
+          <div class="lesson-text lh-copy" v-html="parsedText"></div>
+        </section>
+        <section v-if="concepts" class='dn db-ns ba border-green ph4 ml3 ml5-l mt5 mb3 mr3 measure' style="background: rgba(105, 196, 205, 10%)">
+          <h2 class="f5 fw2 green mt0 nb1 pt3">Useful concepts</h2>
+          <div class='f6 lh-copy' v-html="parsedConcepts"></div>
+        </section>
       </div>
-    </header>
+      <section v-if="exercise" v-bind:class="{expand: expandExercise}" class="exercise pb4 pt3 ph3 ph4-l mb3 mr5 flex flex-column" style="background: #F6F7F9;">
+        <div class="flex-none">
+          <h2 class="mt0 mb2 green fw4 fill-current">
+            <span style='vertical-align:-1px'>
+              <img v-if="lessonPassed" src="../images/complete.svg" alt="complete" style="height: 1rem;"/>
+              <img v-else-if="cachedCode" src="../images/in-progress.svg" alt="complete" style="height: 1rem;"/>
+              <img v-else src="../images/not-started.svg" alt="not yet started" style="height: 1rem;"/>
+            </span>
+            <span class="green ttu f6 pl2 pr1 fw7 v-mid">
+              <span v-if="lessonPassed">You did it!</span>
+              <span v-else-if="cachedCode">Keep working.</span>
+              <span v-else>Try it!</span>
+            </span>
+            <span class="green f6 fw5 v-mid">
+              <span v-if="cachedCode && !lessonPassed">{{cachedStateMsg}}</span>
+            </span>
+            <div class="fr">
+              <button
+                v-if="expandExercise"
+                title="go smol"
+                v-on:click="toggleExpandExercise"
+                class='b--transparent bg-transparent green hover-green-muted pointer focus-outline'>
+                <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" viewBox="0 0 32 32"><path d="M16 4 L28 4 L28 16 L24 12 L20 16 L16 12 L20 8z M4 16 L8 20 L12 16 L16 20 L12 24 L16 28 L4 28z"></path></svg>
+              </button>
+              <button
+                v-else
+                v-on:click="toggleExpandExercise"
+                title='embiggen the exercise'
+                class='b--transparent bg-transparent charcoal-muted hover-green pointer focus-outline'>
+                <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" viewBox="0 0 32 32"><path d="M16 4 L28 4 L28 16 L24 12 L20 16 L16 12 L20 8z M4 16 L8 20 L12 16 L16 20 L12 24 L16 28 L4 28z"></path></svg>
+              </button>
 
-    <div class="flex-l items-start bt border-aqua bw4">
-      <section class="pv3 indent-1">
-        <h1 class="f3 measure-wide">{{lessonTitle}}</h1>
-        <div class="lh-solid v-mid">
-          <span class="green v-mid"><span class="b">{{workshopShortname}}</span> | Lesson {{lessonNumber}} of {{lessonsInWorkshop}}</span>
-          <span class="pl1"><img v-if="lessonPassed" src="../images/complete.svg" alt="complete" style="height: 1.2rem;" class="v-mid"/></span>
+            </div>
+          </h2>
+          <div v-if="exercise" v-html="parsedExercise" class='lh-copy'></div>
         </div>
-        <div class="lesson-text lh-copy measure-wide" v-html="parsedText"></div>
-      </section>
-      <section v-if="concepts" class='dn db-ns ba border-green ph4 ml3 ml5-l mt5 mb3 mr3 measure' style="background: rgba(105, 196, 205, 10%)">
-        <h2 class="f5 fw2 green mt0 nb1 pt3">Useful concepts</h2>
-        <div class='f6 lh-copy' v-html="parsedConcepts"></div>
-      </section>
-    </div>
-
-    <section v-bind:class="{expand: expandExercise}" class="indent-1 exercise pb4 pt3 ph3 ph4-l mb3 mr5 flex flex-column" style="background: #F6F7F9;">
-      <div class="flex-none">
-        <h2 class="mt0 mb2 green fw4 fill-current">
-          <span style='vertical-align:-1px'>
-            <img v-if="lessonPassed" src="../images/complete.svg" alt="complete" style="height: 1rem;"/>
-            <img v-else-if="cachedCode" src="../images/in-progress.svg" alt="complete" style="height: 1rem;"/>
-            <img v-else src="../images/not-started.svg" alt="not yet started" style="height: 1rem;"/>
-          </span>
-          <span class="green ttu f6 pl2 pr1 fw7 v-mid">
-            <span v-if="lessonPassed">You did it!</span>
-            <span v-else-if="cachedCode">Keep working.</span>
-            <span v-else>Try it!</span>
-          </span>
-          <span class="green f6 fw5 v-mid">
-            <span v-if="cachedCode && !lessonPassed">{{cachedStateMsg}}</span>
-          </span>
-          <div class="fr">
-            <button
-              v-if="expandExercise"
-              title="go smol"
-              v-on:click="toggleExpandExercise"
-              class='b--transparent bg-transparent green hover-green-muted pointer focus-outline'>
-              <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" viewBox="0 0 32 32"><path d="M16 4 L28 4 L28 16 L24 12 L20 16 L16 12 L20 8z M4 16 L8 20 L12 16 L16 20 L12 24 L16 28 L4 28z"></path></svg>
-            </button>
-            <button
-              v-else
-              v-on:click="toggleExpandExercise"
-              title='embiggen the exercise'
-              class='b--transparent bg-transparent charcoal-muted hover-green pointer focus-outline'>
-              <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" viewBox="0 0 32 32"><path d="M16 4 L28 4 L28 16 L24 12 L20 16 L16 12 L20 8z M4 16 L8 20 L12 16 L16 20 L12 24 L16 28 L4 28z"></path></svg>
-            </button>
-
+        <div>
+          <span v-if="cachedCode" v-on:click="resetCode" class="textLink fr pb1">Reset Code</span>
+        </div>
+        <div class="bg-white flex-auto" style='height:100%;'>
+          <MonacoEditor
+            class="editor"
+            srcPath="."
+            :height="editorHeight"
+            :options="options"
+            :code="code"
+            theme="vs"
+            language="javascript"
+            @mounted="onMounted"
+            @codeChange="onCodeChange">
+          </MonacoEditor>
+        </div>
+        <div class='flex-none'>
+          <div class="pv2">
+            <div v-if="output.test && this.cachedCode" v-bind="output.test">
+              <div class="lh-copy pv2 ph3 bg-red white" v-if="output.test.error">
+                Error: {{output.test.error.message}}
+              </div>
+              <div class="lh-copy pv2 ph3 bg-red white" v-if="output.test.fail">
+                {{output.test.fail}}
+              </div>
+              <div class="lh-copy pv2 ph3 bg-green white" v-if="output.test.success && lessonPassed">
+                {{output.test.success}}
+                <a v-if="output.test.cid"
+                class="link fw7 underline-hover dib ph2 mh2 white"  target='explore-ipld' :href='exploreIpldUrl'>
+                  View in IPLD Explorer
+                </a>
+              </div>
+            </div>
+            <div class="lh-copy pv2 ph3" v-else>
+            Update the code to complete the exercise. Click <strong>submit</strong> to check your answer.
+            </div>
           </div>
-        </h2>
-        <div v-if="exercise" v-html="parsedExercise" class='lh-copy'></div>
-      </div>
-      <div>
-        <span v-if="cachedCode" v-on:click="resetCode" class="textLink fr pb1">Reset Code</span>
-      </div>
-      <div class="bg-white flex-auto" style='height:100%;'>
-        <MonacoEditor
-          class="editor"
-          srcPath="."
-          :height="editorHeight"
-          :options="options"
-          :code="code"
-          theme="vs"
-          language="javascript"
-          @mounted="onMounted"
-          @codeChange="onCodeChange">
-        </MonacoEditor>
-      </div>
-      <div class='flex-none'>
-        <div class="pv2">
-          <div v-if="output.test && this.cachedCode" v-bind="output.test">
-            <div class="lh-copy pv2 ph3 bg-red white" v-if="output.test.error">
-              Error: {{output.test.error.message}}
+          <div class="pt3 ph2 tr">
+            <div v-if="((output.test && output.test.success) || lessonPassed) && lessonNumber === lessonsInWorkshop">
+              <Button v-bind:click="workshopMenu" class="bg-aqua white">More Tutorials</Button>
             </div>
-            <div class="lh-copy pv2 ph3 bg-red white" v-if="output.test.fail">
-              {{output.test.fail}}
+            <div v-else-if="lessonPassed">
+              <Button v-bind:click="next" class="bg-aqua white">Next</Button>
             </div>
-            <div class="lh-copy pv2 ph3 bg-green white" v-if="output.test.success && lessonPassed">
-              {{output.test.success}}
-              <a v-if="output.test.cid"
-              class="link fw7 underline-hover dib ph2 mh2 white"  target='explore-ipld' :href='exploreIpldUrl'>
-                View in IPLD Explorer
-              </a>
+            <div v-else>
+              <Button v-bind:click="run" class="bg-aqua white">Submit</Button>
             </div>
           </div>
-          <div class="lh-copy pv2 ph3" v-else>
-          Update the code to complete the exercise. Click <strong>submit</strong> to check your answer.
-          </div>
         </div>
-        <div class="pt3 ph2 tr">
-          <div v-if="((output.test && output.test.success) || lessonPassed) && lessonNumber === lessonsInWorkshop">
+      </section>
+      <section v-else >
+        <div class="pt3 ph2 tr mb3">
+          <div v-if="lessonNumber === lessonsInWorkshop">
             <Button v-bind:click="workshopMenu" class="bg-aqua white">More Tutorials</Button>
           </div>
-          <div v-else-if="lessonPassed">
-            <Button v-bind:click="next" class="bg-aqua white">Next</Button>
-          </div>
           <div v-else>
-            <Button v-bind:click="run" class="bg-green white">Submit</Button>
+            <Button v-bind:click="next" class="bg-aqua white">Next</Button>
           </div>
         </div>
-      </div>
-    </section>
-    <section class="indent-1 mb4 mw-900">
-      <div>
+      </section>
+    </div>
+    <footer class="bg-navy white ph2 ph3-ns mt4 flex items-center justify-around">
+      <div class="mw7">
         <p>Feeling stuck? We'd love to hear what's confusing so we can improve
         this lesson. Please <a :href="issueUrl" target="_blank">share your questions and feedback</a>.</p>
       </div>
-    </section>
+    </footer>
   </div>
 </template>
 
@@ -125,6 +128,7 @@ import Vue from 'vue'
 import MonacoEditor from 'vue-monaco-editor'
 import Explorer from './Explorer.vue'
 import Button from './Button.vue'
+import Header from './Header.vue'
 const IPFS = require('ipfs')
 const CID = require('cids')
 const marked = require('marked')
@@ -181,7 +185,8 @@ export default {
   components: {
     MonacoEditor,
     Explorer,
-    Button
+    Button,
+    Header
   },
   data: self => {
     return {
@@ -198,7 +203,6 @@ export default {
       lessonKey: 'passed' + self.$route.path,
       lessonPassed: !!localStorage['passed' + self.$route.path],
       lessonTitle: self.$attrs.lessonTitle,
-      issueUrl: `https://github.com/ipfs-shipyard/proto.school/issues/new?labels=question&title=Question+on+Lesson+${self.$route.path.slice(self.$route.path.lastIndexOf('/') + 1)}:+${self.$attrs.lessonTitle}+(${self.$route.path})&body=Have%20a%20question%20or%20suggestion%20regarding%20a%20ProtoSchool%20lesson%3F%20Please%20use%20this%0Atemplate%20to%20share%20it!%0A%0A1.%20URL%20of%20the%20lesson%20that's%20confusing%3A%0A%20https%3A%2F%2Fproto.school%2F%23${self.$route.path}%0A%0A2.%20What%27s%20confusing%20about%20this%20lesson%3F%0A%0A3.%20What%20additional%20context%20could%20we%20provide%20to%20help%20you%20succeed%3F%0A%0A4.%20What%20other%20feedback%20would%20you%20like%20to%20share%20about%20ProtoSchool%3F%0A`,
       output: self.output,
       IPFS,
       expandExercise: false,
@@ -221,7 +225,19 @@ export default {
       return parseInt(this.$route.path.slice(this.$route.path.lastIndexOf('/') + 1), 10)
     },
     workshopShortname: function () {
-      return this.$route.path.charAt(1).toUpperCase() + this.$route.path.slice(2, this.$route.path.lastIndexOf('/'))
+      let shortname = this.$route.path.charAt(1).toUpperCase() + this.$route.path.slice(2, this.$route.path.lastIndexOf('/'))
+      // // ADD THIS LATER IF WE DECIDE WE WANT ALL WORDS CAPITALIZED
+      // if (shortname.includes("-")) {
+      //   let shortnameArray = shortname.split("-")
+      //   let shortnameArrayUpper = shortnameArray.map( word => {
+      //     return (word.charAt(0).toUpperCase() + word.slice(1))
+      //   })
+      //   shortname = shortnameArrayUpper.join(" ")
+      // }
+      return shortname.split('-').join(" ")
+    },
+    issueUrl: function () {
+      return `https://github.com/ProtoSchool/protoschool.github.io/issues/new?assignees=&labels=lesson-feedback&template=lesson-feedback.md&title=Lesson+Feedback%3A+${this.workshopShortname}+-+Lesson+${this.lessonNumber}+(${this.lessonTitle})`
     },
     lessonsInWorkshop: function () {
       let basePath = this.$route.path.slice(0, -2)
@@ -336,13 +352,23 @@ export default {
       }
     },
     next: function () {
-      Vue.set(this.output, 'test', null)
+      if (this.exercise) {
+        Vue.set(this.output, 'test', null)
+      } else {
+        localStorage[this.lessonKey] = 'passed'
+        this.lessonPassed = !!localStorage[this.lessonKey]
+      }
       let current = this.lessonNumber
       let next = (parseInt(current) + 1).toString().padStart(2, '0')
       this.$router.push({path: next})
     },
     workshopMenu: function () {
-      Vue.set(this.output, 'test', null)
+      if (this.exercise) {
+        Vue.set(this.output, 'test', null)
+      } else {
+        localStorage[this.lessonKey] = 'passed'
+        this.lessonPassed = !!localStorage[this.lessonKey]
+      }
       this.$router.push({path: '/'})
     },
     toggleExpandExercise: function () {
@@ -384,6 +410,10 @@ span.textLink {
   text-decoration: underline;
 }
 
+footer a {
+  color: aqua;
+}
+
 @media screen and (min-width: 60rem) {
   .indent-1 {
     margin-left: 93px;
diff --git a/src/components/Navigation.vue b/src/components/Navigation.vue
index 2c90fa403..90e496f4f 100644
--- a/src/components/Navigation.vue
+++ b/src/components/Navigation.vue
@@ -1,7 +1,12 @@
 <template>
   <section class="flex items-center bg-aqua white pv3"
     <div class="bg-aqua w-100">
-      <nav class="flex items-center bg-aqua white pv3 center tc mw7">
+      <nav v-if="isLesson" class="flex items-center bg-aqua navy pv3 center tc mw7">
+        <router-link class="nav-link navy" :to="'/'">Home</router-link> >
+        <router-link class="nav-link navy" :to="'/tutorials'">Tutorials</router-link> >
+        <span class="fake-nav-link">{{workshopShortname}}</span>
+      </nav>
+      <nav v-else class="flex items-center bg-aqua white pv3 center tc mw7">
         <div v-for="link in links">
           <router-link v-if="link.path === $route.path"
            class="nav-link white" :to="`${link.path}`">{{link.text}}</router-link>
@@ -19,6 +24,8 @@ export default {
   name: 'Navigation',
   data: self => {
     return {
+      currentPath: self.$route.path.toString(),
+      workshopShortname: (self.$route.path.charAt(1).toUpperCase() + self.$route.path.slice(2, self.$route.path.lastIndexOf('/'))).split('-').join(" "),
       links: [
         {
           text: 'Home',
@@ -46,7 +53,22 @@ export default {
         }
       ]
     }
-  }
+    },
+    computed: {
+      isLesson: function () {
+        let count = 0
+        this.links.forEach( link => {
+          if (link.path === this.currentPath) {
+            count++
+          }
+        })
+        if (count === 0) {
+          return true
+        } else {
+          return false
+        }
+      }
+    }
 }
 </script>
 
@@ -59,6 +81,13 @@ export default {
   margin: 2px 20px;
   text-decoration: none;
 }
+.fake-nav-link {
+  font-size: 18px;
+  font-weight: 700;
+  margin: 2px 20px;
+  text-decoration: none;
+  color: white;
+}
 .nav-link:first {
   margin: 2px 20px 2px 0px;
 }
diff --git a/src/components/home/Home.vue b/src/components/home/Home.vue
index d71c4eef0..c0a0b34bd 100644
--- a/src/components/home/Home.vue
+++ b/src/components/home/Home.vue
@@ -13,9 +13,16 @@
           <router-link class="f5 link dim br-pill ph3 pv2 mb2 dib white bg-navy mr3" to="/tutorials">View All Tutorials</router-link>
           <router-link class="f5 link dim br-pill ph3 pv2 mb2 dib white bg-navy" to="/build">Build a Tutorial</router-link>
         </div>
-
         <h2>Featured Tutorials</h2>
         <div id="featured" class="flex flex-wrap justify-between">
+          <div class="bg-aqua br4 pa3 mb3 tutorial-tile">
+            <router-link to="/data-structures/01">
+              <h3 class="ma0 f3 fw7 navy">Decentralized Data Structures</h3>
+              <p class="f5 fw5 ma0 pt2 lh-copy white">
+                The decentralized web relies on unique data structures and linking strategies. Learn about the benefits of hashing, content addressing, DAG and Merkle Trees!
+              </p>
+            </router-link>
+          </div>
           <div class="bg-aqua br4 pa3 mb3 tutorial-tile">
             <router-link to="/basics/01">
               <h3 class="ma0 f3 fw7 navy">P2P data links with content addressing</h3>
@@ -24,7 +31,6 @@
               </p>
             </router-link>
           </div>
-
           <div class="bg-aqua br4 pa3 mb3 tutorial-tile">
             <router-link to="/blog/01">
               <h3 class="ma0 f3 fwy navy">Blogging on the Decentralized Web</h3>
@@ -33,7 +39,6 @@
               </p>
             </router-link>
           </div>
-
         </div>
 
         <h1>Chapter Events</h1>
diff --git a/src/components/tutorials/Tutorials.vue b/src/components/tutorials/Tutorials.vue
index 1f527a38a..52575c84f 100644
--- a/src/components/tutorials/Tutorials.vue
+++ b/src/components/tutorials/Tutorials.vue
@@ -9,6 +9,38 @@
           the decentralized web by writing code and solving challenges.
         </p>
       </section>
+      <section class="db mw7 center ph2">
+        <div class="flex items-start pv4">
+          <div class="project-label flex-none tc">
+            <h1 class="ma0 f3 fw6 pb2">IPFS</h1>
+            <img src="../../images/ipfs.svg" alt="" style="height: 54px"/>
+          </div>
+          <div class="w-100">
+            <h2 class="ma0 f3 fw5"><router-link to="/data-structures/01">Decentralized data structures</router-link></h2>
+            <p class="f5 fw5 ma0 pt2 lh-copy charcoal-muted">
+              The decentralized web relies on unique data structures and linking strategies. Learn about the benefits of hashing, content addressing, DAG and Merkle Trees!
+            </p>
+            <ul class="mv4 pa0 f5" style="list-style-type: none; background: rgba(11, 58, 82, 5%)">
+              <li>
+                <ExerciseLink to="/data-structures/01" index="1" name="Data structures" />
+              </li>
+              <li>
+                <ExerciseLink to="/data-structures/02" index="2" name="The centralized web: Location-based addressing" />
+              </li>
+              <li>
+                <ExerciseLink to="/data-structures/03" index="3" name="The decentralized web: Content addressing" />
+              </li>
+              <li>
+                <ExerciseLink to="/data-structures/04" index="4" name="Cryptographic hashing and Content Identifiers (CIDs)" />
+              </li>
+              <li>
+                <ExerciseLink to="/data-structures/05" index="5" name="Merkle trees and directed acyclic graphs (DAG)" />
+              </li>
+
+            </ul>
+          </div>
+        </div>
+      </section>
       <section class="db mw7 center ph2">
         <div class="flex items-start pv4">
           <div class="project-label flex-none tc">
diff --git a/src/lessons/Data-Structures/01.md b/src/lessons/Data-Structures/01.md
new file mode 100644
index 000000000..9866cefd8
--- /dev/null
+++ b/src/lessons/Data-Structures/01.md
@@ -0,0 +1,33 @@
+## Welcome to ProtoSchool!
+
+Before diving into code challenges, let's take a minute to look at a few of the
+concepts that underly the decentralized web. Unlike our other tutorials, this one is
+code-free and designed especially to introduce you to some of the key terms you'll
+encounter throughout ProtoSchool.
+
+Let's get started!
+
+
+## Data structures
+
+Whether you're a programmer or not, you're surrounded by data structures every day. Lists, dictionaries, and catalogs all help us organize information and take into account the relationships between various pieces of data.
+
+From [Wikipedia](https://en.wikipedia.org/wiki/Data_structure):
+
+> In computer science, a data structure is a data organization, management and storage format that enables efficient access and modification.[1][2][3] More precisely, a data structure is a collection of data values, the relationships among them, and the functions or operations that can be applied to the data.
+
+In programming, data structures are everywhere. The way you organize data into variables in order to use them in programs involves any from dozens to millions of data structures. If you're a developer, you're probably familiar with common data structures like arrays, objects, graphs, etc.
+
+## Decentralized data structures
+
+On the decentralized web, where we access data directly from our peers rather than
+from a central authority, we need specialized data structures that allow us to verify
+and link between various pieces of content.
+
+Data structures that are using decentralized systems need to be **verifiable**. On a single
+system you have a much greater degree of trust in the data structures you work with in memory
+or on disc. But in a decentralized system you have less, or possibly zero, trust among peers.
+
+Also, large data structures need to be able to be spread out among peers and **linked together**
+in order to be decentralized. In the same way that any web page can link to another web page
+in a different location, decentralized data structures enable a web of interlinked data.
diff --git a/src/lessons/Data-Structures/01.vue b/src/lessons/Data-Structures/01.vue
new file mode 100644
index 000000000..e42aad164
--- /dev/null
+++ b/src/lessons/Data-Structures/01.vue
@@ -0,0 +1,24 @@
+<template>
+  <div class="lesson-01">
+  <Lesson v-bind:text="text" v-bind:code="code"
+          :validate="validate"
+          lessonTitle="Data structures">
+    </Lesson>
+  </div>
+</template>
+
+<script>
+import Lesson from '../../components/Lesson'
+import text from './01.md'
+
+export default {
+  components: {
+    Lesson
+  },
+  data: () => {
+    return {
+      text
+    }
+  }
+}
+</script>
diff --git a/src/lessons/Data-Structures/02.md b/src/lessons/Data-Structures/02.md
new file mode 100644
index 000000000..be794d2dc
--- /dev/null
+++ b/src/lessons/Data-Structures/02.md
@@ -0,0 +1,21 @@
+
+Before we dig into how sharing works on the decentralized web, let's take a minute to examine how we're accustomed to accessing data.
+
+## Location addressing with URLs
+
+URLs (Uniform Resource Locators) are the primary addresses we give each other for data on the centralized web (you know, that plain old web we're all used to). They make it possible for us to create links and connect data on the web, so they serve a valuable purpose. (The web would be pretty lousy without links!) However, <strong>URLs are based on the <em>location</em> where data is stored</strong>, not on the contents of the resource stored there. We call this <strong>location addressing</strong>, and it presents us with some problems.
+
+Most of us have a lot of experience with URLs, and we make some assumptions about them based on our experience. When we see  `https://www.puppies.com/beagle.jpg`, for example, we'll probably guess from the file name and extension that
+the data stored at that location is an image (in JPEG format) of a beagle, but we can't verify this from the URL alone. There may very well be a photo of a chihuahua hiding at `beagle.jpg`, or even worse, an adorable kitty!
+
+Through the domain name, URLs indicate the *authority* we should ask for the data. Even though the web is already decentralized, in that anyone can link to anyone else, the location-based references we use for those links require that the data itself be centralized so that we can get it from an authority. We make assumptions about these authorities or domains as well. For example, we'd assume that a file hosted at `puppies.com` is safer to open than one hosted at `evilhacker.com`, but we can't be sure of it.
+
+All of this uncertainty also works in reverse. If we see a picture of an adorable puppy and are told it's stored on the web, there's no way for us to guess the URL that would lead us to the image. We can neither determine the domain, which tells us who's hosting it, nor the filename.
+
+## Trust and efficiency on the centralized web
+As you can see, since we can't verify what content resides at a particular URL and are dependent on central authorities (and human kindess) to label things as they really are, it's easy for us to get tricked.
+
+It's also easy for 42,000 people to store exactly the same photo of an adorable beagle, all on different domains and with different filenames. Let's face it, even on our own laptops most of us have accidentally saved that save document as `download.pdf` and `download(01).pdf` without realizing it, or saved iterations of
+the same term paper over and over again with `v1` or `2018-12-18` added to the title. The web is a confusing mess of data that's saved multiple times at different URLs, and there's no easy way to tell which items are identical to each other.
+
+There must be a better way!
diff --git a/src/lessons/Data-Structures/02.vue b/src/lessons/Data-Structures/02.vue
new file mode 100644
index 000000000..6e7f03ef1
--- /dev/null
+++ b/src/lessons/Data-Structures/02.vue
@@ -0,0 +1,24 @@
+<template>
+  <div class="lesson-02">
+  <Lesson v-bind:text="text" v-bind:code="code"
+          :validate="validate"
+          lessonTitle="Location addressing and the centralized web">
+    </Lesson>
+  </div>
+</template>
+
+<script>
+import Lesson from '../../components/Lesson'
+import text from './02.md'
+
+export default {
+  components: {
+    Lesson
+  },
+  data: () => {
+    return {
+      text
+    }
+  }
+}
+</script>
diff --git a/src/lessons/Data-Structures/03.md b/src/lessons/Data-Structures/03.md
new file mode 100644
index 000000000..a172483ba
--- /dev/null
+++ b/src/lessons/Data-Structures/03.md
@@ -0,0 +1,58 @@
+As we've seen, the centralized web relies on central authorities
+to host our data and uses URLs as addresses to access it. But location
+addressing isn't the only option. On the
+<strong>decentralized web</strong>, we can all host each other's data,
+and there's a different kind of linking that's more secure, making it easy to
+trust our neighbors.
+
+## Crytographic hashing
+
+<strong>[Cryptographic hashing](https://en.wikipedia.org/wiki/Cryptographic_hash_function)</strong> is the
+most important tool in the toolbox of decentralized data structures. It opens the door to a new form of linking, known as <strong>content
+addressing</strong>, that we can use in a decentralized environment without central authorities.
+
+Hashing takes data of any size and returns you a single fixed-size "hash" for that data.
+A hash is a string of characters that looks like gobbledygook, but you can think of it
+as a name for the data. It might look something like this:
+
+`zdpuAsHkamdCQgrDrNSwJVgjMkQWoLxdrccxV6qe9htipNein`
+
+To be honest, these content-derived names aren't currently very friendly to humans
+(`beagle.jpg` was so much more descriptive!), but they're a lot more secure. Here's why:
+
+<strong>Cryptographic hashes can be derived from the content of the data itself</strong>,
+meaning that anyone using the same
+algorithm on the same data will arrive at the same hash. If Ada and Grace
+are both using the same decentralized web protocol, such as IPFS, to share the exact
+same photo of a kitten, both images will have exactly the same hash. By comparing
+those hashes and confirming they're identical, we can guarantee that every single pixel
+of those two photos is identical.
+
+<strong>Cryptographic hashes are also unique</strong>. That means that if Grace uses Photoshop to remove a
+single whisker from that kitty, the updated image will have a new hash, and it will
+be easy to tell &mdash; just from the hash, without access to the file itself &mdash; that it
+contains different data.
+
+## Trust on the decentralized web
+
+On the centralized web, we've learned to trust certain authorities and not others. We do our best
+with the clues we have from URLs, but there are some malicious actors who use the shortcomings of location
+addressing to trick us.
+
+On the decentralized web, where we're all able to pitch in and host each other's data, we may not
+know much about the <em>peers</em> who are hosting data, but content addressing gives us a way to trust
+the data that they're sharing. With content addressing, we can't be fooled by malicious actors into
+accessing the wrong data. That's what makes cryptographic hashing so important to the decentralized web.
+
+## Asking peers for content
+
+With traditional location addressing, we knew we needed to visit the domain `puppies.com` to find the
+content stored as `beagle.jpg`. If the `puppies.com` domain were broken for some reason, we'd lose
+access to that image.
+
+The decentralized web works differently. When we want a specific photo of an adorable pet, we ask for it
+by its content address (hash). Who do we ask? The whole network! If Ada is online, we'll see that she has
+the content we're looking for, which we can verify as being exactly what we're looking for because it has
+a matching hash. If she goes offline, we may still be able to get the same photo from Grace or another peer.
+
+Since we use hashes to request data on the decentralized web, we can think of a hash as a link, not just a name.
diff --git a/src/lessons/Data-Structures/03.vue b/src/lessons/Data-Structures/03.vue
new file mode 100644
index 000000000..c48859db8
--- /dev/null
+++ b/src/lessons/Data-Structures/03.vue
@@ -0,0 +1,24 @@
+<template>
+  <div class="lesson-03">
+  <Lesson v-bind:text="text" v-bind:code="code"
+          :validate="validate"
+          lessonTitle="Content addressing with cryptographic hashes">
+    </Lesson>
+  </div>
+</template>
+
+<script>
+import Lesson from '../../components/Lesson'
+import text from './03.md'
+
+export default {
+  components: {
+    Lesson
+  },
+  data: () => {
+    return {
+      text
+    }
+  }
+}
+</script>
diff --git a/src/lessons/Data-Structures/04.md b/src/lessons/Data-Structures/04.md
new file mode 100644
index 000000000..82e5bc899
--- /dev/null
+++ b/src/lessons/Data-Structures/04.md
@@ -0,0 +1,50 @@
+
+So far we've exclusively been discussing adorable images for the sake of our general
+merriment, but content addressing can be used on all different types of files and data,
+from JSON objects to term papers to videos. For cryptographic hashing to work, we need
+to know what data format we're working with and use an appropriate tool.
+
+## Decoding data structures
+
+A `CID` is a particular form of content addressing. It's a specification developed for
+IPFS, a specific decentralized web protocol that we'll discuss in later tutorials,
+but it has very broad implications.
+
+A `CID` is a single identifier that contains a cryptographic hash **and**
+information about how to interpret that data called a "codec." Codecs encode and
+decode data in certain formats.
+
+```
++-------+------------------------------+
+| Codec | Multihash                    |
++-------+------------------------------+
+```
+
+Many formats and protocols use content addressing. `CID` allows us to create a universal identifier for any of these systems. Tools like git and protocols like Ethereum and Bitcoin all use content addressing already, but they differ in how to interpret the data and what cryptographic function they use for hashing.
+
+A `CID` is an identifier that contains the `codec` to interpret the data and a `multihash` which is a self-desribing hash (a hash that tells you what type of hashing function was used to create it).
+
+```
++------------------------------+
+|Codec                         |
++------------------------------+
+|Multihash                     |
+| +----------+---------------+ |
+| |Hash Type | Hash Value    | |
+| +----------+---------------+ |
+|                              |
++------------------------------+
+```
+
+## Linking between different data structures
+
+`CID`s allow us to build data structures that link to other data structures
+in completely different formats. Imagine a tree of JSON objects that link
+to BSON objects than also link to git commits. (Or imagine a file folder containing
+puppy images <em>and</em> kitty videos, with a subfolder containing articles on
+giraffes. The possiblities are endless!) All the way down this tree we
+have cryptographic hashes that allow us to distribute and link the data.
+
+Why is it important to link between different data structures? Every day on the centralized web,
+we link from text to images, from logos to homepages, and from emails to PDFs.
+Links tie resources together, convey meaning, and make the web awesomely interactive!
diff --git a/src/lessons/Data-Structures/04.vue b/src/lessons/Data-Structures/04.vue
new file mode 100644
index 000000000..69a7531e0
--- /dev/null
+++ b/src/lessons/Data-Structures/04.vue
@@ -0,0 +1,24 @@
+<template>
+  <div class="lesson-04">
+  <Lesson v-bind:text="text" v-bind:code="code"
+          :validate="validate"
+          lessonTitle="Content Identifiers (CIDs)">
+    </Lesson>
+  </div>
+</template>
+
+<script>
+import Lesson from '../../components/Lesson'
+import text from './04.md'
+
+export default {
+  components: {
+    Lesson
+  },
+  data: () => {
+    return {
+      text
+    }
+  }
+}
+</script>
diff --git a/src/lessons/Data-Structures/05.md b/src/lessons/Data-Structures/05.md
new file mode 100644
index 000000000..f048d2a1e
--- /dev/null
+++ b/src/lessons/Data-Structures/05.md
@@ -0,0 +1,60 @@
+
+As we've discussed, the decentralized web depends on linked data structures. Let's explore
+what those look like.
+
+## Merkle trees
+A merkle tree, or simple "hash tree," is a tree data structure in which every node is hashed.
+
+```
+               +--------+
+               |        |
+     +---------+  root  +---------+
+     |         |        |         |
+     |         +----+---+         |
+     |              |             |
++----v-----+  +-----v----+  +-----v----+
+|          |  |          |  |          |
+|  node A  |  |  node B  |  |  node C  |
+|          |  |          |  |          |
++----------+  +-----+----+  +-----+----+
+                    |             |
+              +-----v----+  +-----v----+
+              |          |  |          |
+              |  node D  |  |  node E  +-------+
+              |          |  |          |       |
+              +----------+  +-----+----+       |
+                                  |            |
+                            +-----v----+  +----v-----+
+                            |          |  |          |
+                            |  node F  |  |  node G  |
+                            |          |  |          |
+                            +----------+  +----------+
+```
+
+In a merkle tree, nodes point to other nodes by content address (hash). Remember,
+when we run data through a cryptographic hash, we get back a "hash" or "content address"
+that we can think of as a link, so a merkle tree is a collection of linked nodes.
+
+As previously discussed, all content addresses are unique. In the graph above, `node E` contains a reference to the hash for `node F` and `node G`.
+This means that the content address (hash) of `node E` is unique to a node containing those addresses.
+
+Getting lost? Let's imagine this as a set of file folders. If we run folder E through our hashing algorithm
+while it contains subfolders F and G, the content-derived hash we get back is unique to its current content.
+If we remove folder G, it's like Grace removing that whisker from her kitten photo. The folder formerly known as E doesn't
+have the same contents anymore, so it gets a new hash.
+
+As the tree above is built, the final content address (hash) of the root node is unique to a
+tree than contains every node all the way down this tree. If the data in any node were
+to change even by a single byte, the hash of the changed node would change, as would the hashes
+of all of its parent nodes.
+
+In case you haven't noticed, this means that as a programmer you'll always need to build
+these data structures backwards, from the leaf nodes on up to the root node.
+
+## Directed Acyclic Graphs (DAG)
+
+![img](https://upload.wikimedia.org/wikipedia/commons/c/c6/Topological_Ordering.svg)
+
+DAG is an acronym for "Directed Acyclic Graph." It's a fancy way of describing a
+specific kind of merkle tree (hash tree) where different branches in the tree can point at other branches
+in the tree in a single forward direction, as illustrated by the image above.
diff --git a/src/lessons/Data-Structures/05.vue b/src/lessons/Data-Structures/05.vue
new file mode 100644
index 000000000..121b864b7
--- /dev/null
+++ b/src/lessons/Data-Structures/05.vue
@@ -0,0 +1,24 @@
+<template>
+  <div class="lesson-05">
+  <Lesson v-bind:text="text" v-bind:code="code"
+          :validate="validate"
+          lessonTitle="Merkle trees and Directed Acyclic Graphs (DAG)">
+    </Lesson>
+  </div>
+</template>
+
+<script>
+import Lesson from '../../components/Lesson'
+import text from './05.md'
+
+export default {
+  components: {
+    Lesson
+  },
+  data: () => {
+    return {
+      text
+    }
+  }
+}
+</script>
diff --git a/src/main.js b/src/main.js
index 08945c0c7..20b83f530 100644
--- a/src/main.js
+++ b/src/main.js
@@ -21,6 +21,11 @@ import LessonBlog04 from './lessons/Blog/04.vue'
 import LessonBlog05 from './lessons/Blog/05.vue'
 import LessonBlog06 from './lessons/Blog/06.vue'
 import LessonBlog07 from './lessons/Blog/07.vue'
+import LessonDataStructures01 from './lessons/Data-Structures/01.vue'
+import LessonDataStructures02 from './lessons/Data-Structures/02.vue'
+import LessonDataStructures03 from './lessons/Data-Structures/03.vue'
+import LessonDataStructures04 from './lessons/Data-Structures/04.vue'
+import LessonDataStructures05 from './lessons/Data-Structures/05.vue'
 
 Vue.use(VueRouter)
 
@@ -31,6 +36,11 @@ const routes = [
   { path: '/host', component: Host, name: "Host" },
   { path: '/build', component: Build, name: "Build" },
   { path: '/contribute', component: Contribute, name: "Contribute" },
+  { path: '/data-structures/01', component: LessonDataStructures01 },
+  { path: '/data-structures/02', component: LessonDataStructures02 },
+  { path: '/data-structures/03', component: LessonDataStructures03 },
+  { path: '/data-structures/04', component: LessonDataStructures04 },
+  { path: '/data-structures/05', component: LessonDataStructures05 },
   { path: '/basics/01', component: LessonBasics01 },
   { path: '/basics/02', component: LessonBasics02 },
   { path: '/basics/03', component: LessonBasics03 },