The first returns a “real” boolean value, because you first negate what is inside the parenthesis, but then immediately negate it again. So, it’s like saying something is “not not” truth-y, making it true. The second example simply checks for the existence of the obj1 and obj2, but might not necessarily return a “real” boolean value, instead returning something that is either truth-y or false-y. This can be problematic, because false-y can be the number 0, or an empty string, etc. Simple existence can be truth-y. A “real” boolean will only be true or false.
