Mostly when I do a blueprint I follow my lecture or tutorial. When I ask them when and why to use that variable, they answer “just follow it and you will understand”.
But to me, I don’t think I understand. I watch and look at every tutorial and some notes I still do not understand. They give the answer not I really want.
I know it sounds stupid but I really want to understand. So… if anyone is kind heart or helpful, can anyone drop the easy or the detail about the each variable.
For example, the bool is for ‘if the nodes are working or not’. So when will use that and why?
The same goes for the rest of the variables.
Also what difference between Local Variables and Promote the Variable?
You use variables to suit your needs. A bool can only hold true or false, so when that’s all you need, you use a bool.
When you want to store numbers, you use an integer. But if you want to store all the little bits in between, then a float.
And so on.
You can promote a pin to a variable. It just saves you making the variable and dragging the pin onto it. If you are promoting a variable inside a function, then there’s the option to ‘promote to local variable’. This is a variable that only exists inside that function. If you try to refer to it outside, it won’t work.
If I recall correctly, if you press ALT+CTRL while your mouse is over a variable type. (When you create it in the blueprint variable panel) a pop up will show up which will give more information on what that variable does.
I’ve used this to understand when one needs to use a string, a name, or text.
Thank you for the comment and why I didn’t notice that feature 
Anyway thank you