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+# ADT's
+
+Limbo supports Abstract Data Types (ADT's). These are analogous, but not equivocal to, structs in C and Go. 
+
+For further reading on ADT's and how they compose in different contexts, see [Modules](../Modules) and [Generics](../Generics).
+
+## Source
+
+### adts.b:12,16
+
+The type `Person` is an ADT declared within a module definition possessing an integer, string, and function reference member. 
+
+The function is named stringify and takes an argument named `p` which is a reference to the adt variable instance which called the function. This function could be thought as being analogous to a method. 
+
+Method-like function references declared with `self` as a keyword for an argument are not required to be called with said argument being passed. 
+
+Note: Modules are a form of ADT with some special rules associated with them that differentiates them from a normal ADT.
+
+### adts.b:19,23
+
+The type `Town` is an ADT declared outside of a module definition possessing an array of references to Person ADT's, a string, and a function reference. 
+
+### adts.b:28,29
+
+The variable `p` is created as a reference to an instance of a `Person` type which is instantiated using constructor-like syntax. The `Person` element `name` is then printed. 
+
+Note: Although the syntax used to instantiate the `Person` type instance appears to be a function, it is closer to a tuple being passed into an instance of a `Person`, but used in an in-line fashion. That is, the tuple must contain all non-function reference types contained within the ADT. 
+
+### adts.b:31,36
+
+The variable `t` is created as an instance of a `Town` ADT. The non-function reference elements are then initialized manually. Note that the `ref Person(...)` instantiation can be used as a valid variable instance. 
+
+### adts.b:41,52
+
+The method-like function references are declared with a bit of special syntax. That is, the function name takes the form of `ADT.func()`. 
+
+## Demo
+
+	; adts
+	Spike
+	Name: Mars
+	Size: 2
+	Members:
+	→ Spike
+	→ Ed
+	; 
+
+## Exercises
+
+- Can you instantiate an ADT via its constructor without all its non-function reference members?
+- How would you format the constructor-style instantiation of a `ref Town`?