diff --git a/branches.md b/branches.md
index d4cd1f0f40a229030969931a92f15c0737e39e6a..4e77d236f3781aa984ff5fe1c747fcc42a4a3836 100644
--- a/branches.md
+++ b/branches.md
@@ -2,7 +2,7 @@
 
 Branch-off within the same repository in order to stay safe!
 
-The master branch:
+<br><br>The master branch
 <img src="img/branch-master.png" class="branch-master" />
 
 
@@ -23,7 +23,7 @@ $ git push
 ```
 
 
-If you do that, `git` will complain
+If you do that, `git` might complain
 ```bash
 fatal: The current branch matrix_vect_mult_myName has no upstream branch.
 To push the current branch and set the remote as upstream, use
diff --git a/essential_commands.md b/essential_commands.md
index 25aa3f01972b5d705541a616dce18daeef822cba..606266ffb170531ce218dec1d7b240d4f9c0dc7a 100644
--- a/essential_commands.md
+++ b/essential_commands.md
@@ -52,7 +52,7 @@ Then, uncomment the line
 <br>
 Save and rename the file by adding your name
 ```bash
-mv firstCommit/addTwoNumbers.m firstCommit/addTwoNumbers_myName.m
+$ mv firstCommit/addTwoNumbers.m firstCommit/addTwoNumbers_myName.m
 ```
 
 
diff --git a/list.json b/list.json
index 3dd91a69ad4768b5ea07c3f8da6cea90a0377624..eaa96734b211027b930937950a0663fedcb4f60d 100644
--- a/list.json
+++ b/list.json
@@ -23,6 +23,12 @@
           "data-background": "../img/whiteBG.jpg"
         }
     },
+    {
+        "filename": "why_use_git.md",
+        "attr": {
+          "data-background": "../img/whiteBG.jpg"
+        }
+    },
     {
         "filename": "installation.md",
         "attr": {
@@ -64,5 +70,11 @@
         "attr": {
           "data-background": "../img/whiteBG.jpg"
         }
+    },
+    {
+        "filename": "ready.md",
+        "attr": {
+          "data-background": "../img/whiteBG.jpg"
+        }
     }
 ]
diff --git a/ready.md b/ready.md
new file mode 100644
index 0000000000000000000000000000000000000000..d4f8b4110ec78265070753f22795253911c55b8c
--- /dev/null
+++ b/ready.md
@@ -0,0 +1 @@
+# Ready for a practice!!!
diff --git a/thanks.md b/thanks.md
index 62ab5a8b254e4a3ab6310be343153329efe08e2c..bb4d48c17612cedebeecae9a8c9c5c651866feeb 100644
--- a/thanks.md
+++ b/thanks.md
@@ -6,20 +6,3 @@
 ### Cheat sheet
 [Web](http://rogerdudler.github.io/git-guide/index.html) or [PDF](http://rogerdudler.github.io/git-guide/files/git_cheat_sheet.pdf)
 
-
-## Acknowledgement
-
-<table style="text-align:center; width:500px;
-    position:fixed;
-    margin-left:-250px; /* half of width */
-    left:50%;">
- <tr>
-    <th>![](https://avatars0.githubusercontent.com/u/20812112?v=3&s=220)</th>
-    <th>![](https://avatars1.githubusercontent.com/u/816318?v=3&s=220)</th> 
-  </tr>
-  <tr>
-    <th>Laurent Heirendt</th>
-    <th>Sylvain Arreckx</th> 
-  </tr>
- 
-</table>
diff --git a/what_is_git.md b/what_is_git.md
index 44347eed70d4fbbc10d2ac5fdeed14f94d0cedd7..378da33ee52e2766833d2e1fe27c1ec5e7a14bc1 100644
--- a/what_is_git.md
+++ b/what_is_git.md
@@ -1,10 +1,10 @@
 ## What is `git`?
 
-![](img/git_definition.png)
+<!-- ![](img/git_definition.png) -->
 
 `git` is a **version control system** (VCS) for tracking changes in computer files and coordinating work on those files among multiple people [1].
 
-Designed and implemented in 2005 by **Linus Torvalds**
+<br><br><br>Designed and implemented in 2005 by **Linus Torvalds**
 
 ![](img/linus.jpg)
 
diff --git a/why_use_git.md b/why_use_git.md
new file mode 100644
index 0000000000000000000000000000000000000000..848e8dea532336eb3b219623639e19bb6a7c6ee4
--- /dev/null
+++ b/why_use_git.md
@@ -0,0 +1,6 @@
+# Why use git?
+
+* keep the changes you made over time
+* allow you to backtrack (if necessary) and undo those changes
+* easily add contributions of your collaborators to the main code base
+