What is Boolean in JavaScript

Answer 1

Boolean is a type of variable.
It's values are either true or false.

Example-
var isOnline = true;
var x = false;

Answer 2

It is a logical data type that has 'True' or 'False' as values

Answer 3

This is data type, mostly used to make some switch(to turn on and off something)
And to check some condition, like in if/else, js can convert other data types like numbers, strings to boolean values, you will learn more about it in course.