Declaring a boolean in JavaScript using just var

Question

If I declare a JavaScript boolean variable like this:

var IsLoggedIn;

And then initialize it with either true or 1

Answer 1

The variable will become what ever type you assign it. Initially it is undefined. If you assign it 'true' it will become a string, if you assign it true it will become a boolean, if you assign it 1 it will become a number. Subsequent assignments may change the type of the variable later.