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@@ -23,4 +23,10 @@ Example: composing processes. Mathematical functions, algorithms, physical proce
 
 ![[Pasted image 20210530135825.png]]
 
-Notation: 
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+Notation: boxes instead of arrows. Directionality is from left to right.
+
+![[Pasted image 20210530135906.png]]
+
+The output of the first box is the same [[type]] as the input of the second.
+
+![[Pasted image 20210530135937.png]]
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