What does typeof operator do?
The typeof operator returns the data type of a variable or an expression. It is a unary operator that is placed before its operand.
const book = {
title: 'JavaScript',
author: 'John Doe',
};
console.log(typeof book); // objectWhat does keyof operator do?
The keyof operator returns the keys of a type. It is used to get the keys of an object type.
type Book = {
title: string;
author: string;
};
type BookKeys = keyof Book; // 'title' | 'author'