How many methods are there to create variables, how do they differ?

[#1]

As a beginner at QlikView, I recently learned of 2 methods to create variables:

1. Load Script (EX: set vtest = 1, let vtest2 = today() etc.)
2. Variable Overview Menu (EX: Settings => Variable Overview)

My questions are thus:

1. Are there any other ways variables can be created?
   1. Perhaps in a sheet object expression?
2. What are the differences between variables created using various different methods?
   1. A difference I found was that variables created through the Variable Overview Menu don't automatically show up on load scripts, so if a load script is passed along to someone else and the script calls on a variable created through the Variable Overview Menu, the script may encounter error when running in a new QlikView environment.
3. What is the best practice when it comes to which method to use to create variables? Should all variables be defined in the load script or Variable Overview Menu?
   

Thanks!

[maxgro]

Are there any other ways variables can be created?

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external source: qvw, excel, database table

Variables

What is the best practice when it comes to which method to use to create variables? Should all variables be defined in the load script or Variable Overview Menu?

IMHO external

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