What are Truthy and Falsy Values in JavaScript?

Understanding JavaScript Truthy and Falsy Values

In JavaScript, certain values are evaluated as either truthy or falsy in Boolean contexts. These evaluations are crucial for conditional statements, logical operations, and other aspects of the language.

Regarding the sample data you provided:

1. var a = 0: Falsy. Zero evaluates to false in a Boolean context.
2. var a = 10 == 5: Falsy. The comparison operator == returns true if the values are equal. Since 10 is not equal to 5, it evaluates to false.
3. var a = 1: Truthy. Non-zero numbers are truthy.
4. var a = -1: Truthy. Negative numbers are also truthy.

MDN Definition of Truthy and Falsy:

According to MDN (Mozilla Developer Network), a truthy value evaluates to true when used in a Boolean context, while all other values are considered falsy.

List of Falsy Values in JavaScript:

1. false
2. null
3. undefined
4. 0
5. NaN
6. '' (Empty string)
7. Empty string
8. document.all
9. 0n (BigInt)
10. -0

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