Update 'Interface Definitions'

Interface-Definitions.md

@@ -1,17 +1,21 @@
+# Syntax
+```
+face ro ReadWriter:Face
+	write
+		> data:{Byte ..}
+		< wrote:Int
+		< err:Error
+	read
+		> into:{Byte ..}
+		< read:Int
+		< err:Error
+```
+
+Interface sections contain a list of behaviors. Behaviors are a name followed by an indented block of inputs and outputs. It is essentially a more stripped down version of function syntax.
+
+# Semantics
 Interfaces in ARF are like interfaces in Go, that is to say, their methods are
 defined and any object that has at least those methods can fulfill that
 interface.
 
-They are defined like this:
-
-```
-face ro ReadWriter:Face
-	read
-		> into:{Byte ..}
-		< amountRead:Size
-	write
-		> buffer{Byte ..}
-		< amountWrote:Size
-```
-
 Interfaces are able to inherit other interfaces using type notation. If an interface inherits nothing, it must inherit `Face`, which is a blank interface.