JavaScript Callbacks Explained: Passing Functions as Arguments

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A callback in JavaScript is a function passed as an argument to another function, which then invokes it at the appropriate time. This is possible because JavaScript treats functions as values, allowing them to be stored in variables, passed around, or returned from other functions. Callbacks are particularly useful in asynchronous operations, such as with setTimeout(), where code needs to execute only after a task completes. A key distinction exists between passing a function reference like execute(greet) versus calling it immediately with execute(greet()), as the two behave differently. Understanding callbacks is foundational to grasping broader JavaScript concepts including event handling, promises, and built-in array methods.

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Developer builds AI agent in 70 lines of Python, then exposes its security flaw

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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