Chapter 2. The JavaScript Asynchronous Model

In this chapter, we will look at the model behind asynchronous programming, why it was needed, and how it is implemented in JavaScript.

We will also learn what a programming model is and its significance, starting from a simple programming model to a synchronous model to an asynchronous model. Since our prime focus is on JavaScript, which employs an asynchronous programming model, we will discuss it in more detail than the rest of the models.

Let's start with what models are and their significance.

Models are basically templates upon which the logics are designed and fabricated within a compiler/interpreter of a programming language so that software engineers can use these logics in writing their software logically. Every programming language we use is designed on a particular programming model. Since software engineers are asked to solve a particular problem or to automate any particular service, they adopt programming languages as per the need.

There is no set rule that assigns a particular language to create products. Engineers adopt any language based on the need.