diff --git a/.obsidian/workspace b/.obsidian/workspace
index 7cc50d7..fbd234b 100644
--- a/.obsidian/workspace
+++ b/.obsidian/workspace
@@ -89,13 +89,13 @@
   "lastOpenFiles": [
     "School/Analyse/Layers/1. Physical Layer.md",
     "School/Analyse/Comminucation Mediums.md",
-    "School/Analyse/Images/modulation-frequency.png",
     "School/Analyse/Images/modulation-amplitude.png",
+    "School/Analyse/Images/modulation-phase-2.png",
+    "School/Analyse/Images/modulation-phase.png",
+    "School/Analyse/Images/modulation-frequency.png",
     "School/Analyse/Images/encoder.png",
     "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/6. Presentation Layer.md"
   ]
 }
\ No newline at end of file
diff --git a/School/Analyse/Images/modulation-phase-2.png b/School/Analyse/Images/modulation-phase-2.png
new file mode 100644
index 0000000..27f428a
Binary files /dev/null and b/School/Analyse/Images/modulation-phase-2.png differ
diff --git a/School/Analyse/Images/modulation-phase.png b/School/Analyse/Images/modulation-phase.png
new file mode 100644
index 0000000..cd48657
Binary files /dev/null and b/School/Analyse/Images/modulation-phase.png differ
diff --git a/School/Analyse/Layers/1. Physical Layer.md b/School/Analyse/Layers/1. Physical Layer.md
index 71ebbe7..a4f2bba 100644
--- a/School/Analyse/Layers/1. Physical Layer.md	
+++ b/School/Analyse/Layers/1. Physical Layer.md	
@@ -37,12 +37,20 @@ This can be done in 3 different ways.
 ![[modulation-amplitude.png]]
 
 Amplitude or the strength (height) of a wave changes over time.
-We can change how much the amplitude is changing in a specific moment in time.
 
 ### Frequency
 ![[modulation-frequency.png]]
 
-Frequency can be changed 
+Frequency is the amount of waves that pass a fixed point in a given amount of time.
+
+### Phase
+![[modulation-phase.png]]
+
+Phase specifies the location or timing of a point within a wave cycle of a repetitive waveform.
+
+![[modulation-phase-2.png]]
+
+## Analog data
 
 
-### Phase
\ No newline at end of file
+## Digital data
\ No newline at end of file