What does the apply function do in JavaScript?

Calls a function with a specified this value and arguments provided as an array (or array-like object).

Main uses:

• Changing the execution context of the function (this).
• Passing arguments as an array.

Comparison with call and bind:

Method	Arguments	this context	Return
apply	Array/array-like object	Set	Result of the function call
call	Separate arguments (comma-separated)	Set	Result of the function call
bind	Separate arguments (comma-separated)	Set	New function with bound context

Example usage:

// Function definition
function greet(greeting, name) {
  console.log(`${this.title} ${greeting}, ${name}!`);
}

const person = { title: 'Mr.' };
const args = ['Hello', 'Alice'];

// Call function with changed context and arguments from array
greet.apply(person, args); // Outputs: Mr. Hello, Alice!