Do not differ

Differ in the presence of loops

Differ in all cases

May differ in the presence of exception

At most one activation record exists between the current activation record and the activation record for the main

The number of activation records between the current activation record and the activation record of the main depends on the actual function calling sequence.

The visibility of global variables depends on the actual function calling sequence.

Recursion requires the activation record for the recursive function to be saved on a different stack before the recursive fraction can be called.

The complement of a recursively language is recursive.

The complement of a recursively enumerable language is recursively enumerable.

The complement of a recursively language is either recursive or recursively enumerable.

The complement of a context-free language is context-free.

A context free language

A context sensitive language

A regular language

Parsable fully only by a Turing machine