diff --git a/categories.html b/categories.html
index 2ae191e..1292044 100644
--- a/categories.html
+++ b/categories.html
@@ -73,7 +73,7 @@
 <ul style="font-size: 2em; font-weight:bold">
     <li><span class="yellow">Why?
 <ul class="base01" style="border-left: 2px solid; padding-left: 1em; font-size: .6em; float: right; font-weight: bold; margin: 0 0 0 1em">
-    <li>About this presentation</li>
+    <li>General overview</li>
     <li>Math <span class="and"><span class="and">&amp;</span></span> Abstraction</li>
     <li>Programming <span class="and"><span class="and">&amp;</span></span> Abstraction</li>
     <li>Categories <span class="and"><span class="and">&amp;</span></span> Abstraction</li>
@@ -84,7 +84,7 @@
 </ul>
 </section>
 <section class="slide">
-<h2 id="category-theory">Category Theory</h2>
+<h2 id="category-theory-high-level">Category Theory: High level</h2>
 <ul>
 <li>Central position in contemporary mathematics/computer science/physics.</li>
 <li>General mathematical theory of structures and of systems of structures.</li>
@@ -97,36 +97,23 @@
 </ul>
 </section>
 <section class="slide">
-<h2 id="about-this-presentation">About this presentation</h2>
-<ul>
-<li>A lot of slides, but short with pictures,</li>
-<li>General Ideas → Definitions → Examples using Haskell,</li>
-<li>About very fundamental Math, but I'll try not to digress.</li>
-</ul>
+<img src="categories/img/head_explode.jpg" alt="head explode" style="width: 80%"/>
 </section>
 <section class="slide">
-<h2 id="category-theory-goal">Category Theory Goal?</h2>
-<p>Many different approach about Category Theory:</p>
-<ul>
-<li><a href="http://math.ucr.edu/home/baez/rosetta.pdf">Homogeneous vocabulary and notations</a></li>
-<li><a href="http://math.ucr.edu/home/baez/rosetta.pdf">Bridge between disciplines</a></li>
-<li><a href="http://www.math.harvard.edu/~mazur/preprints/when_is_one.pdf">Better definition of equality</a></li>
-<li><a href="www.math.harvard.edu/~mazur/preprints/when_is_one.pdf">Generalization by default</a></li>
-<li>Better math foundations</li>
-</ul>
-</section>
-<section class="slide">
-<h2 id="what-can-category-theory-do-for-us">What can Category Theory do for us?</h2>
+<h2 id="category-theory-for-programming">Category Theory for programming?</h2>
+<img class="right" src="categories/img/buddha.png" alt="buddha"/>
 <ul>
 <li>Ability to see problem differently</li>
-<li>Ability to abstract at the right level</li>
-<li>Reduce bugs by separating concepts</li>
+<li>Make generalisation easier</li>
+<li>Help code organisation</li>
+<li>Reduce bugs by clarifying concepts</li>
 </ul>
-<p>What did they already done?</p>
+<p>Example In Haskell:</p>
 <ul>
-<li>Functors, Applicative Functor, Monads, Arrows</li>
-<li>Generalize <code>fold</code></li>
-<li>...</li>
+<li>Functors</li>
+<li>Monads</li>
+<li><code>fold</code> generalisation</li>
+<li>Applicative Functors, Arrows, ...</li>
 </ul>
 </section>
 <section class="slide">
diff --git a/categories/10_Introduction/020_Plan.html b/categories/10_Introduction/020_Plan.html
index 0b3134d..ed68722 100644
--- a/categories/10_Introduction/020_Plan.html
+++ b/categories/10_Introduction/020_Plan.html
@@ -2,7 +2,7 @@
 <ul style="font-size: 2em; font-weight:bold">
     <li><span class="yellow">Why?
 <ul class="base01" style="border-left: 2px solid; padding-left: 1em; font-size: .6em; float: right; font-weight: bold; margin: 0 0 0 1em">
-    <li>About this presentation</li>
+    <li>General overview</li>
     <li>Math <span class="and">&amp;</span> Abstraction</li>
     <li>Programming <span class="and">&amp;</span> Abstraction</li>
     <li>Categories <span class="and">&amp;</span> Abstraction</li>
diff --git a/categories/10_Introduction/030_Category_Theory.html b/categories/10_Introduction/030_Category_Theory.html
index 52d7c52..1e9cd55 100644
--- a/categories/10_Introduction/030_Category_Theory.html
+++ b/categories/10_Introduction/030_Category_Theory.html
@@ -1,4 +1,4 @@
-<h2 id="category-theory">Category Theory</h2>
+<h2 id="category-theory-high-level">Category Theory: High level</h2>
 <ul>
 <li>Central position in contemporary mathematics/computer science/physics.</li>
 <li>General mathematical theory of structures and of systems of structures.</li>
diff --git a/categories/10_Introduction/030_Category_Theory.md b/categories/10_Introduction/030_Category_Theory.md
index 4768cf7..8f878d6 100644
--- a/categories/10_Introduction/030_Category_Theory.md
+++ b/categories/10_Introduction/030_Category_Theory.md
@@ -1,5 +1,5 @@
-Category Theory
----------------
+Category Theory: High level
+---------------------------
 
 - Central position in contemporary mathematics/computer science/physics.
 - General mathematical theory of structures and of systems of structures.
diff --git a/categories/10_Introduction/040_About_this_presentation.html b/categories/10_Introduction/040_About_this_presentation.html
deleted file mode 100644
index 74213f7..0000000
--- a/categories/10_Introduction/040_About_this_presentation.html
+++ /dev/null
@@ -1,6 +0,0 @@
-<h2 id="about-this-presentation">About this presentation</h2>
-<ul>
-<li>A lot of slides, but short with pictures,</li>
-<li>General Ideas → Definitions → Examples using Haskell,</li>
-<li>About very fundamental Math, but I'll try not to digress.</li>
-</ul>
diff --git a/categories/10_Introduction/040_About_this_presentation.md b/categories/10_Introduction/040_About_this_presentation.md
deleted file mode 100644
index 2e9a616..0000000
--- a/categories/10_Introduction/040_About_this_presentation.md
+++ /dev/null
@@ -1,6 +0,0 @@
-About this presentation
------------------------
-
-- A lot of slides, but short with pictures,
-- General Ideas → Definitions → Examples using Haskell,
-- About very fundamental Math, but I'll try not to digress.
diff --git a/categories/10_Introduction/040_head_explode.html b/categories/10_Introduction/040_head_explode.html
new file mode 100644
index 0000000..db0022f
--- /dev/null
+++ b/categories/10_Introduction/040_head_explode.html
@@ -0,0 +1 @@
+<img src="categories/img/head_explode.jpg" alt="head explode" style="width: 80%"/>
diff --git a/categories/10_Introduction/050_Category_Theory_Goal.html b/categories/10_Introduction/050_Category_Theory_Goal.html
deleted file mode 100644
index 206a5b7..0000000
--- a/categories/10_Introduction/050_Category_Theory_Goal.html
+++ /dev/null
@@ -1,9 +0,0 @@
-<h2 id="category-theory-goal">Category Theory Goal?</h2>
-<p>Many different approach about Category Theory:</p>
-<ul>
-<li><a href="http://math.ucr.edu/home/baez/rosetta.pdf">Homogeneous vocabulary and notations</a></li>
-<li><a href="http://math.ucr.edu/home/baez/rosetta.pdf">Bridge between disciplines</a></li>
-<li><a href="http://www.math.harvard.edu/~mazur/preprints/when_is_one.pdf">Better definition of equality</a></li>
-<li><a href="www.math.harvard.edu/~mazur/preprints/when_is_one.pdf">Generalization by default</a></li>
-<li>Better math foundations</li>
-</ul>
diff --git a/categories/10_Introduction/050_Category_Theory_Goal.md b/categories/10_Introduction/050_Category_Theory_Goal.md
deleted file mode 100644
index d74cee3..0000000
--- a/categories/10_Introduction/050_Category_Theory_Goal.md
+++ /dev/null
@@ -1,10 +0,0 @@
-Category Theory Goal?
----------------------
-
-Many different approach about Category Theory:
-
-- [Homogeneous vocabulary and notations](http://math.ucr.edu/home/baez/rosetta.pdf)
-- [Bridge between disciplines](http://math.ucr.edu/home/baez/rosetta.pdf)
-- [Better definition of equality](http://www.math.harvard.edu/~mazur/preprints/when_is_one.pdf)
-- [Generalization by default](www.math.harvard.edu/~mazur/preprints/when_is_one.pdf)
-- Better math foundations
diff --git a/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.html b/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.html
index 371a1cf..6ff010e 100644
--- a/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.html
+++ b/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.html
@@ -1,12 +1,15 @@
-<h2 id="what-can-category-theory-do-for-us">What can Category Theory do for us?</h2>
+<h2 id="category-theory-for-programming">Category Theory for programming?</h2>
+<img class="right" src="categories/img/buddha.png" alt="buddha"/>
 <ul>
 <li>Ability to see problem differently</li>
-<li>Ability to abstract at the right level</li>
-<li>Reduce bugs by separating concepts</li>
+<li>Make generalisation easier</li>
+<li>Help code organisation</li>
+<li>Reduce bugs by clarifying concepts</li>
 </ul>
-<p>What did they already done?</p>
+<p>Example In Haskell:</p>
 <ul>
-<li>Functors, Applicative Functor, Monads, Arrows</li>
-<li>Generalize <code>fold</code></li>
-<li>...</li>
+<li>Functors</li>
+<li>Monads</li>
+<li><code>fold</code> generalisation</li>
+<li>Applicative Functors, Arrows, ...</li>
 </ul>
diff --git a/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.md b/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.md
index a6dc587..575feb3 100644
--- a/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.md
+++ b/categories/10_Introduction/060_What_can_Category_Theory_do_for_us.md
@@ -1,12 +1,16 @@
-What can Category Theory do for us?
------------------------------------
+Category Theory for programming?
+--------------------------------
+
+<img class="right" src="categories/img/buddha.png" alt="buddha"/>
 
 - Ability to see problem differently
-- Ability to abstract at the right level
-- Reduce bugs by separating concepts
+- Make generalisation easier
+- Help code organisation
+- Reduce bugs by clarifying concepts
 
-What did they already done?
+Example In Haskell:
 
-- Functors, Applicative Functor, Monads, Arrows
-- Generalize `fold`
-- ...
+- Functors
+- Monads
+- `fold` generalisation
+- Applicative Functors, Arrows, ...
diff --git a/categories/img/mindblown.gif b/categories/img/mindblown.gif
new file mode 100644
index 0000000..221715c
Binary files /dev/null and b/categories/img/mindblown.gif differ