Variable help!!!

Hi, you can call me dumb but i dont know how do variables work! :( I know that they are inportent so i need to know how to use them! Plzz explane it to me!
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Try checking in tutorials for help first.
In brief: variables store data. The type of data it stores depends on the type of variable. Integer data are numbers without decimals while real data has decimals. Boolean is true/false. The other types are relatively easy to understand. You use the set variable action to give variables data and you can use the variables in conditions. You could also predetermine what goes in the variable.