# 11.3. Recursion Summary¶

In this unit you learned about recursion. A recursive method calls itself (contains a call to the method from inside of the method). A recursive method should have at least one way to stop the recursion. This is called a base case.

## 11.3.1. Concept Summary¶

• base case - A way to stop the recursive calls. This is a return without a recursive call.

• call stack - A class defines what all objects of that class know (fields) and can do (methods). You can also have data and behavior in the object that represents the class (class fields and methods). All objects of a class have access to class fields and class methods, but these can also be accessed using className.field or className.method().

• recursive method - A method that contains at least one call to itself inside the method.

## 11.3.3. Common Mistakes¶

• Missing the recursive call. Be sure to look for a call to the same method.

• Getting confused about when a recursive method returns and what it returns.

• Assuming you understand what the recursion is doing without tracing all of it.