Before a variable can be set, it must be declared. Variables are declared with the
var keyword, followed by one or more comma-delimited variable names. For example, if you need to define a member’s first name, last name and membership expiry date, the variables could be declared as:
var @firstName, @lastName, @membershipExpiryDate
Declaring a variable adds an entry to an internal Variables Dictionary, using the variable name as the key and
null as the value. If an entry for that name already exists, the value of the variable will be reset to
NOTE: AMPscript is a loosely typed language and as a result, the interpreter does not enforce variables to be declared. However, it’s best practice to do so, to ensure the variable name is added to the Variables Dictionary.