Dynamic programming with a local function:

Euclid's algorithm for the GCD using initialized local variables:

Every time a module is evaluated, a new temporary symbol is created:

Module symbols are temporary and are removed if they are no longer referenced:

Each use of Module increments $ModuleNumber:

If there is no need to assign to a local variable, a constant should be used instead:

With is faster than Module:

Block localizes values only; it does not create new symbols:

Unique creates new variables in a way similar to Module:

Local variables are not affected by global ones, and vice versa:

A symbol brought into the scope of Module is not affected by naming conflicts:

Module is a scoping construct; inner local variables shield outer ones:

Variables are renamed in nested scopes:

Build the function from its parts to avoid the renaming:

Parallel assignment is not available for Module variables: