A synchronous request is an HTTP request that blocks the server until the response is returned. The majority of the services on the web run in this fashion. Nowadays, with the advent of distributed systems and loose coupling, API requests can also be asynchronous. In other words, an asynchronous request returns with information that can be used to fetch the information of a process. These asynchronous requests on a server are closely related to how concurrently the server can execute a job for multiple clients. Let's look at what a synchronous request looks like:

In this type of request, the web server performs all the actions and returns an Immediate Response to the Web client/Mobile client. The drawback of this approach is that if the server takes too much time to render the result, the client is blocked on the server's action...