Essential Books

Convert a number to a boolean

suggest change 
Boolean(0) === false

Boolean(0) will convert the number 0 into a boolean false.

A shorter, but less clear, form: 

!!0 === false
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Variable coercion / conversion:
*Remarks
*Double negation (!!x)
*Implicit conversion
*Convert to boolean
*Convert string to number
*Convert string to boolean
*Convert string to float
*Convert a number to a boolean
*Convert array to a string
*Array to string using array methods
*Integer to Float
*Float to Integer
*Converting a number to a string
*Primitive to primitive conversion table
Table Of Contents
0Getting started
1Comments
2Basic data types
3Built-in constants
4Variables
5Declarations and assignments
6Reserved keywords
7Data types in JavaScript
8Strings
9Escape sequences
10Template Literals
11Arrays
12Objects
13Prototypes objects
14Classes
15Variable coercion / conversion
16Map
17Set
18Arithmetic Math
19Bitwise operators
20Bitwise operators
21Unary Operators
22Comparison operations
23Conditions
24Loops
25Functions
26Arrow functions
27Date
28Date comparison
29Scope
30AJAX
31Promises
32Regular Expression
33Error Handling
34Geolocation
35Cookies
36Intervals and timeouts
37Generators
38History of visited urls
39Strict mode
40Custom Elements
41JSON
42Binary Data
43Web Storage
44Fetch
45Modules
46Screen
47Inheritance
48Timestamps
49Destructuring assignment
50Web Worker
51Debugging
52Notifications API
53WebSockets
54Web Cryptography API
55Async functions, async / await
56Constructor functions
57execCommand and contenteditable
58Performance Tips
59Design patterns
60requestAnimationFrame
61Method chaining
62Global error handling in browsers
63File API, blobs and FileReaders
64Console
65Tail call optimization
66Detecting browser
67Enumerations
68Symbols
69Localization
70Selection API
71Callbacks
72Functional JavaScript
73Modals
74Data attributes
75Event Loop
76Events
77Data manipulation
78BOM Browser Object Model
79Unit Testing
80Linters for ensuring code quality
81Automatic Semicolon Insertion
82IndexedDB
83Anti-patterns
84Navigator Object
85Modularization techniques
86Proxy
87Same origin policy, cross-origin communication
88postMessage and MessageEvent
89WeakMap
90WeakSet
91Behaviroal Design Patterns
92Server-sent events
93Async iterators
94Namespacing
95Evaluating JavaScript
96Memory efficiency
97How to make iterator usable inside async callback function
98Context this
99Setters and getters
100Vibration API
101Fluent API
102Tilde
103Security issues
104Get and set CSS custom variables
105Contributors