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In JavaScript, a truthy value is a value that is considered  true when evaluated in a Boolean context. All values are truthy unless they are defined as falsy (i.e., except for false, 0, "", null, undefined, and NaN).

JavaScript uses type coercion in Boolean contexts.

Examples of truthy values in JavaScript (which will translate to true and thus execute the if block):

if (true)
if ({})
if ([])
if (42)
if ("foo")
if (new Date())
if (-42)
if (3.14)
if (-3.14)
if (Infinity)
if (-Infinity)

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 Contributors to this page: sgress454, torazaburo, brodybits, Andrew_Pfeiffer, klez, fscholz
 Last updated by: sgress454,