What values are evaluated to false in JavaScript?

Below values are evaluated to false in JavaScript.

a.   false

b.   Undefined

c.   null

d.   0

e.   NaN

f.    the empty string ("")

All the other values are evaluated to true.

HelloWorld.js

var a = false;
var b;
var c = null;
var d = 0;
var e = NaN;
var f = "";

if(a){
  console.log(`${a} is evaluated to true`);
}else{
  console.log(`${a} is evaluated to false`);  
}

if(b){
  console.log(`${b} is evaluated to true`);
}else{
  console.log(`${b} is evaluated to false`);  
}

if(c){
  console.log(`${c} is evaluated to true`);
}else{
  console.log(`${c} is evaluated to false`);  
}

if(d){
  console.log(`${d} is evaluated to true`);
}else{
  console.log(`${d} is evaluated to false`);  
}

if(e){
  console.log(`${e} is evaluated to true`);
}else{
  console.log(`${e} is evaluated to false`);  
}

if(f){
  console.log(`${f} is evaluated to true`);
}else{
  console.log(`${f} is evaluated to false`);  
}

Output

false is evaluated to false

undefined is evaluated to false

null is evaluated to false

0 is evaluated to false

NaN is evaluated to false

 is evaluated to false

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