For the longest time I wanted to learn what AJAX was all about (you can interact with a website’s features without the need of reloading the entire website). The first thing that got me confused was the term “asynchronous”; what’s that about, right?
Now, AJAX is all about asynchronous programming, which means, the client doesn’t have to wait for a server response in order to execute/process another part of the Web application. Remember, with synchronous programming the app follows a recipe style format; perform step 1, then 2, and so on. With an async approach, there isn’t such thing as a recipe style, which means, it doesn’t have to wait for step 1 to finish in order to execute step 2 or 3. This sounds great right? Well, it does! It improves the user experience and performance!
A living example on how AJAX works is by looking at Google Maps website. As you move your cursor to different parts of the page, there are certain tiles/squares that get updated with the new satellite pictures (these are XMLHttpRequest calls to the server). Something very important to take into consideration, is the fact that each tile doesn’t wait for the first one to finish loading and then proceed to the next one and so on, they don’t follow a particular order. That’s why certain tiles load faster than others.
I truly hope this little introduction gave you a better understanding on how AJAX works. This is Part I of my AJAX series. Make sure to come back next week (or subscribe to my newsletter!) for Part II where we will start to write some code!