A single-page application is a website which responds to user interaction by dynamically rewriting the homepage with new data (instead of loading new pages). Its benefits include speed, a smooth user experience, and easy production deployment.
The Definition of a Single-Page Application
A single-page application is literally an application which is only a single page. It’s a pretty descriptive name!
But that doesn’t mean the application looks like a single page. When you click on links on the page, parts of the page will be re-rendered and new data will be downloaded. Under the hood, though, it’s all the same page in a single index.html file.
In other words, the entire single-page application loads once you open the website. Whatever (internal) links you click within the app, you’ll always be interacting with the same HTML template. How the template is filled in, though, will depend on where on the page you navigate.
The Benefits of a Single-Page Application
Single-page applications have many benefits for users as well as for developers.
Benefits for the User
SPAs are fast – at least, after the initial load. Because you don’t have to wait for a full page reload between clicks, things happen almost instantaneously. The experience of using a good SPA is very smooth, like interacting with the real world, without the interference of a clunky device.
SPAs also provide a linear user experience: the apps are usually structured from top to bottom. This makes navigation easy and natural; instead of finding your way through a maze of links, you just need to keep scrolling.
Finally, SPAs’ high caching capabilities allow them to function quite well offline after the initial download.
Benefits for the Developer
SPAs are super easy to deploy. Because an SPA is just a single index.html file together with CSS and JavaScript bundles, all the developer needs to do is upload these three static files to a static content server.
Because SPAs are made of reusable components which can be scaled in response to screen size, they make mobile development easy. And since a linear structure is a natural fit for mobile devices, very little needs to be changed between mobile and desktop versions of SPAs.
An SPA’s frontend is cleanly separated from the backend, allowing the frontend and backend to be developed independently and at the same time.
Finally, version control is easier with SPAs.
Downsides
That’s a lot of benefits, but it’s not all sunshine and roses! The downsides include the following:
- When you first visit an SPA, it can take a long time to load
- Single-page applications can be bad for search-engine optimization.
- SPAs don’t combine well with older browsers.
Would you like to learn more?
Read about: Which Is Best For Single Page Application?
