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@@ -12,4 +12,15 @@ Physical layer is responsible for this conversion. The Physical layer deals with
 
 You could say the physical layer is a bridge between real life and software.
 
-## Waves
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+## Waves
+Waves, like you would see on a lake, or in electrical cables are made when a physical quantity changes in the form of a moving ridge.
+
+Waves by them self store no real information.
+
+## Signal
+A signal is a wave that holds information. (wave + data = signal)
+
+## Encoder
+A encoder converts 
+
+![[Pasted image 20211103214144.png]]
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