Call Apply Bind

The methods call, apply, and bind are used for manual management of the context (this) of a function. They are available to all functions through the Function.prototype prototype.

call()

• Calls the function immediately, passing this and arguments separated by commas.
• Used when you need to call a function with a specific context right now.

func.call(thisArg, arg1, arg2, ...);

apply()

• Similar to call(), but arguments are passed in the form of an array or pseudo-array.
• Convenient when arguments are already in an array (for example, when using Math.max).

func.apply(thisArg, [arg1, arg2, ...]);

bind()

• Does not call the function immediately, but returns a new function with a fixed this and (optionally) partially set arguments.
• Used for deferred call or permanent context binding, for example, in event handlers.

const newFunc = func.bind(thisArg, arg1, arg2, ...);

Key Ideas

• call and apply — execute the function immediately, with different ways of passing arguments.
• bind — does not execute immediately, but returns a new function.
• All three methods allow explicit management of the execution context (this).
• Typical case: loss of context when passing a method as a callback.