Why do we need undefined in JavaScript? What is the purpose of it?
128709
Why is there a `null` value in JavaScript?
132062
Reference undefined
107919
Advantages of using [] over new Array() in JavaScript
55375
What is the $ symbol used for in JavaScript
121807
Const in JavaScript: when to use it and is it necessary?
140402
Do inner functions in JavaScript get hoisted? How do the scoping rules apply to them?
19234
What is the purpose of a self executing function in javascript?
25477
What is "function*" in JavaScript?
16604
What's the purpose (if any) of "javascript:" in event handler tags?
102930
What does "return this" do within a javascript function?
27606
Detecting an undefined object property
47676
What does "var FOO = FOO || {}" (assign a variable or an empty object to that variable) mean in Javascript?
85438
In PHP, what is a closure and why does it use the "use" identifier?
120997
What is the purpose of new Boolean() in Javascript?
317
What is the scope of variables in JavaScript?
105797
Why can't we define a variable inside an if statement?
91633
Why don't we just use element IDs as identifiers in JavaScript?