or vs ?? javascript code example

Example 1: java vs javascript

/*
JavaScript can be used to do neat things like creating 
animation in HTML. ... JavaScript code is run on a 
browser only, while Java creates applications that run 
in a virtual machine or browser. Java is an OOP 
(object-oriented programming) language, and JavaScript is
specifically an OOP scripting language.
*/

Example 2: != vs !== javascript

(0 ==  '0') // true
(0 === '0') // false

('' ==  0 ) // true, the string will implicitly be converted to an integer
('' === 0 ) // false, no implicit cast is being made