Rules for Naming:

-An identifier must be at least one character in length
-The first character must be a letter, underscore ( _ ), or a dollar sign ($).
-Each character after the first can be a letter, underscore, dollar sign or a number.
-Spaces and special characters other than a _ and $ are not allowed in any part of an identifier.

*Variable names often use CamelCase
A good way to name variables with multiple words is with lowerCamelCase.