A brief summary, I hope it is not too cryptic:

€¢ Variable scope:
o Procedural level variable (declared within the procedure and available
only within the procedure).
o Module level variable (declared at the top of the module)
Dim VariableName as Type (Available only within the module).
Private VariableName as Type (Available only within the module).
Public VariableName as Type (Available throughout the project).
€¢ Variable lifetime:
o By default variables retain their assigned value only until the
subroutine in which they are declared executes the exit or end statement.
o If the subroutine or the variable is declared as static the variable
retains its value until the workbook is closed.
o Module level variables are static.

Tom