Scratch

Variable names in themselves don't mean anything. It's just what the programmer names them, so he can refer to them when neccesary. You could change the name of those variables, and as long as you change all the scripts in that project to the new variable name, it wouldn't affect the project at all!

Instead, it is what the programmer does with the variables that is important. For example, the Platform_global_x could be a variable to work out the X position of either the background and or the sprites in a platformer, and offset_x would probably be to offset jumping and non-jumping sprites in a platformer.

Again, those are just guesses. The programmer could have named them cake and cookie and they'd still do the exact same thing.

On a side note, this belongs in either Questions about Scratch or Help with Scripts, so I'll ask for it to be moved there