What JavaScript Values Are Truthy and Which Are Falsy?

Understanding JavaScript Truthy and Falsy

In JavaScript, certain values evaluate to true or false in Boolean contexts. This concept is known as truthiness and falsiness. To understand this, let's examine the code provided:

var a = 0;
var a = 10 == 5;
var a = 1;
var a = -1;

Answers to Your Questions:

Contrary to your belief, only two of the statements result in truthy values:

• var a = 1;: Non-zero numbers, including negative values, are truthy.
• var a = -1;: Negative values are also truthy.

Falsy Values:

The remaining statements evaluate to falsy values:

• var a = 0;: Zero is falsy. (However, note that "0" as a string is truthy)
• var a = 10 == 5;: This is equivalent to (10 == 5), which is a comparison that evaluates to false.

MDN Definition of Truthiness:

As per the Mozilla Developer Network (MDN), a truthy value is one that translates to true when evaluated as a Boolean. All values are considered truthy except for the following:

• false
• null
• undefined
• 0
• NaN
• "" (empty strings)

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