What is JavaScript?

JavaScript often abbreviated as Js, is a lightweight programming or scripting language that is used to make dynamic and interactive web pages.

It is also referred to as an object-based scripting language with first-class functions.

This means functions are treated as values that can be assigned to variables, passed as arguments to other functions, and returned as values from functions. In other words, functions in JavaScript can be used just like any other data type

For instance, you can create a function and assign it to a variable, just like you would assign a string or a number to a variable. You can then pass that variable as an argument to another function or use it as a value in an expression.

const sayHello = function(name) {
  console.log(`Hello, ${name}!`);
};

function greet(greeting, name) {
  greeting(name);
}

greet(sayHello, 'Alice');

In this example, we define a greet function that takes a greeting function as its first argument and a name as its second argument. When we call greet with the sayHello function and the name 'Alice', it calls the sayHello function with the name 'Alice', which logs the message "Hello, Alice!" to the console