$ModuleNumber

$ModuleNumber
gives the current serial number to be used for local variables that are created.

You can reset $ModuleNumber to any positive integer, but if you do so, you run the risk of creating naming conflicts.

Each use of Module increments $ModuleNumber:

You can reset $ModuleNumber:

Each use of Module increments $ModuleNumber:

Out[1]=

You can reset $ModuleNumber:

Out[1]=

Use a unique module number in your Mathematica session:

$ModuleNumber will now increment starting from this number:

$ModuleNumber is also used by Unique to create new symbols from given ones:

If given a string, it creates the first available symbol of the form xnnn: