diff --git a/.obsidian/workspace b/.obsidian/workspace
index 3af1735..2cac0cc 100644
--- a/.obsidian/workspace
+++ b/.obsidian/workspace
@@ -9,7 +9,7 @@
         "state": {
           "type": "markdown",
           "state": {
-            "file": "School/Analyse/Layers/Application Layer.md",
+            "file": "School/Analyse/Layers/1. Physical Layer.md",
             "mode": "source"
           }
         }
@@ -68,7 +68,7 @@
             "state": {
               "type": "backlink",
               "state": {
-                "file": "School/Analyse/Layers/Application Layer.md",
+                "file": "School/Analyse/Layers/1. Physical Layer.md",
                 "collapseAll": false,
                 "extraContext": false,
                 "sortOrder": "alphabetical",
@@ -87,15 +87,15 @@
   },
   "active": "bc6e8ad9aa0f44c3",
   "lastOpenFiles": [
-    "School/Analyse/Layers/Application Layer.md",
-    "School/Analyse/Layers/4. Transport Layer.md",
     "School/Analyse/Layers/1. Physical Layer.md",
+    "School/Analyse/Network Types.md",
+    "School/Analyse/Layers/5. Session Layer.md",
+    "School/Analyse/Layers/6. Presentation Layer.md",
+    "School/Analyse/Layers/7. Application Layer.md",
+    "School/Analyse/Layers/4. Transport Layer.md",
     "School/Analyse/Layers/3. Network Layer.md",
     "School/Analyse/Layers/2. Datalink Layer.md",
-    "School/Analyse/Layers/Presentation Layer.md",
     "School/Analyse/OSI Model.md",
-    "School/Analyse/Comminucation Mediums.md",
-    "School/Analyse/Computer Networks.md",
-    "School/Analyse/Network Software.md"
+    "School/Analyse/Comminucation Mediums.md"
   ]
 }
\ No newline at end of file
diff --git a/School/Analyse/Layers/1. Physical Layer.md b/School/Analyse/Layers/1. Physical Layer.md
index 4e342ae..3e4cd9e 100644
--- a/School/Analyse/Layers/1. Physical Layer.md	
+++ b/School/Analyse/Layers/1. Physical Layer.md	
@@ -3,4 +3,13 @@ This layer is responsible for the actual physical transfer of data between devic
 
 This layer also converts the data into a bit-stream of 1's and 0's. 
 
-The signal convention must be the same on both devices. (Meaning of a 0 and a 1)
\ No newline at end of file
+The signal convention must be the same on both devices. (Meaning of a 0 and a 1)
+
+## In depth
+Information on computers is stored in a digital format. To transmit this information we have to convert the information to signals.
+
+Physical layer is responsible for this conversion. The Physical layer deals with the actual physical transmission of electrical signals.
+
+You could say the physical layer is a bridge between real life and software.
+
+## Waves
\ No newline at end of file
diff --git a/School/Analyse/Layers/Session Layer.md b/School/Analyse/Layers/5. Session Layer.md
similarity index 97%
rename from School/Analyse/Layers/Session Layer.md
rename to School/Analyse/Layers/5. Session Layer.md
index 6a9ca9b..53d7c3b 100644
--- a/School/Analyse/Layers/Session Layer.md	
+++ b/School/Analyse/Layers/5. Session Layer.md	
@@ -1,4 +1,4 @@
-# Session Layer
+# 5. Session Layer
 The session layer is responsible for opening and closing connections between two devices. The duration of a connection is called the session.
 
 The session layer ensures that the connections remains active and open so that the data being received and/or send is complete. 
diff --git a/School/Analyse/Layers/Presentation Layer.md b/School/Analyse/Layers/6. Presentation Layer.md
similarity index 96%
rename from School/Analyse/Layers/Presentation Layer.md
rename to School/Analyse/Layers/6. Presentation Layer.md
index 6a23b3c..8fd0bf2 100644
--- a/School/Analyse/Layers/Presentation Layer.md	
+++ b/School/Analyse/Layers/6. Presentation Layer.md	
@@ -1,4 +1,4 @@
-#  Presentation Layer
+#  6. Presentation Layer
 The presentation layer is responsible for preparing the data so that it can be used by the Application Layer. 
 
 **Presentation layer is responsible for:**
diff --git a/School/Analyse/Layers/Application Layer.md b/School/Analyse/Layers/7. Application Layer.md
similarity index 95%
rename from School/Analyse/Layers/Application Layer.md
rename to School/Analyse/Layers/7. Application Layer.md
index 6a94bbc..133ad6a 100644
--- a/School/Analyse/Layers/Application Layer.md	
+++ b/School/Analyse/Layers/7. Application Layer.md	
@@ -1,4 +1,4 @@
-# Application Layer
+# 7. Application Layer
 The application Layer provides services to the end user. So this is the layer the user actually interacts with. 
 
 These services are usually protocols that interact with the data that the user uses.