Ans :
A constant is a meaningful name that takes the place of a number or string and never changes. VBScript defines a number of intrinsic constants. You can get detailed information about these intrinsic constants from the VBScript Language Reference
Creating Constants
You create user-defined constants in VBScript using the Const statement. This lets you create string or numeric constants with meaningful names and allows you to assign them literal values. For example:
Const MyString = “This is my string.”
Const MyAge = 49
Note that the string literal is enclosed in quotation marks (” “). Quotation marks are the most obvious way to differentiate string values from numeric values. Date literals and time literals are represented by enclosing them in number signs (#). For example:
Const CutoffDate = #6-1-97#
You may want to adopt a naming scheme to differentiate constants from variables. This will save you from trying to reassign constant values while your script is running. For example, you might want to use a “vb” or “con” prefix on your constant names, or you might name your constants in all capital letters. Differentiating constants from variables eliminates confusion as you develop more complex scripts.