[] vs ()

[yane]

In the examples in the documentation and on this forum I encounter 2 different styles of syntax.
For example

Code: Select all

thread.ahkterminate[]

;and

thread.ahkterminate()

What is the difference?
Which one is correct?
When should one be used and when the other?

[HotKeyIt]

Both are correct, you can use either but [] should be very little faster.