Declare variable

Declares a variable to store data while the Flow is executing.

You can declare as many variables as you want
A variable can be either global or local (default). A local variable can only be used within the scope it is declared in. A global variable can be used in the entire Flow, both within Functions and Extension flowcharts.
A variable cannot be referenced unless it is assigned a value. (It will not appear in variable selectors, for example, if you try to use it as an argument to a Function). Note that this is true for both global and local variables.