Calling functions is an advanced feature that I added to the variable editor.
Putting a variable name in [] will tell the game to read its value and store it in the variable specified in the top box.
 [myVar]
You can also read variables inside of objects:
 [myObject.myVar]
If the top box is empty, then the function gets called, but nothing gets stored.
Furthermore, if you put () after the bottom variable, the game will assume it's a function and call it, storing any value it returns in the variable specified in the top box.
This is handy if you want a random number.
 [Math.random()]
This would give you a decimal between 0 and 0.99999
It's also possible to pass values to the function you're calling by putting them inside of the (). Just don't use any spaces becuase they'll be read as part of the string your sending.
 [RAM_F.pokemon.addPokemon(pikachu,1)]
This sends the word "pikachu" and the number "1" to the addPokemon function.
If you want to send a variable to it, enclose it in [], like so:
 [RAM_F.pokemon.addPokemon([myVar],1)]

You can also use [] in the top box if you want a variable to tell the game which variable to store the value in. Confused? Here's an example:
If you type this in the top box:
 [myName]
And myName contains the word "sam", then a variable called sam will be created and it'll contain the value of the lower box.