Intrinsic function are built-in functions by Javascript, sort of like how the notification center is built in to a phone.

Examples of intrinsic functions in JavaScript include:

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Math.sin()

Math.random()

Array.prototype.forEach()

String.prototype.substring()

Object.keys()

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These functions are  are optimized by JavaScript engine and generally are faster and more efficient than custom functions. They also provide a standardized way of performing common tasks, making your code more predictable and easier to maintain