difference between 3d 3d and 3d 3d 3d in javascript

10 == false   // true
20 === false  // false, because they are of a different type
31 == "1"     // true, automatic type conversion for value only
41 === "1"    // false, because they are of a different type
5null == undefined // true
6null === undefined // false
7'0' == false // true
8'0' === false // false