A pot that has nothing in it is called an empty pot whereas if we want to fill it with water later it's not empty anymore!
- If a variable already has a value it can be explicitly cleared off and made null; which means it is empty or the variable is not assigned with any value at the moment.
- We can also assign null to a variable to denote that the variable is purposefully empty at the moment but later can be assigned.
var a; //Undefined console.log(a); a = true; //Defined console.log(a); a = null; //Made Null console.log(a);
Undefined true null
- So basically in first step, we have defined variable a, which when logged will throws an undefined. Undefined is something that occurs when there is no value to the variable.
- After that, we have given a boolean value true to 'a' where it prints the value true.
- During 3rd assignment, We explicitly want the variable 'a' to be empty but not undefined so we have given it a value null. Specifically means that we want the boolean value to be removed.