What is the difference between call(), apply(), and bind() in JavaScript?

Direct answer

call and apply invoke a function immediately with an explicit this value; call receives arguments individually, apply receives an array-like argument list, while bind returns a new function with this and optional leading arguments fixed.

call() and apply() are immediate invocation tools. bind() is a function-creation tool.

fn.call(user, 1, 2) → execute now with this === user and positional arguments.
fn.apply(user, [1, 2]) → execute now with the arguments supplied as an array-like value.
const bound = fn.bind(user, 1) → return a new function; calling bound(2) later supplies the remaining argument.

Modern spread syntax means apply() is less necessary merely to expand an array: fn(...args) is usually clearer when no explicit receiver is needed.