Dim

Dim is short for Dimension statement.

If you're declaring variables, then one way is with the Dim statement:

Examples:

Dim i

Dim i as Integer

Dim s as String

Dim v as Variant

Dim x as Integer, y as Integer

You can declare Arrays by:

Dim a(7) as Integer ' a is an array with 8 elements from 0 to 7

Option Explicit

If a module has this set then all variables must be declared before usage. There are advantages and disadvantages to this:

Pros - Reduces errors because it catches misspellings

Cons - It takes more time to declare variables

Variable Scope

When you declare a variable it's scope can be:

Public - All routines can see the value

Module - Only code in the Module can see the value

Local - The variable is only available to the local Subroutine or function