One of the underlying technologies that plays an important role in how efficiently the internet works is caching. As the name implies, it is simply the temporary storage of files such as html pages, images, and other resources to reduce the number of times we have to request the original. As long as we limit the size of the cache (so it doesn’t become too big) and we check that the original content hasn’t been updated, the system works seamlessly in the background.
The two main kinds of caching are server-side and client-side, with the latter being an integral component of all modern web browsers. Whether you use one or a combination of both depends on how your website has been engineered. In this article we’ll look at how you can use this technology to improve your site’s performance.
Google has emphasised that our latest SEO efforts should focus on making our pages load quickly, especially on mobile devices. Page loading time will affect your search rankings under Google’s new mobile index. If you can get your pages to load in two seconds or less that’s probably a good target. You can use tools like Google’s PageSpeed Insights to test your pages.
To reduce load times you’ll need to pay attention to things like:
- choosing the right kind of host: Shared Resources, Dedicated, or Virtual Private Server (VPS).
- optimising images
- move video content and other downloadable files to dedicated Content Delivery Networks (CDN). Popular options include YouTube and Vimeo for video, and MaxCDN, CloudFare, and Amazon CloudFront for other files.
Content Management Systems (CMS)
One of the most popular solutions for getting a site up and running is to use a platform because you don’t need to be an expert and security is built in. We’ll focus on WordPress here because of its popularity but many of the points might also apply to others such as Joomla, Drupal, and Django.
Behind the scenes a lot happens when you request a page from WordPress. In essence, the page is generated on-the-fly and that means time is consumed on the background processes. Luckily, most platforms allow us to install plugins to help improve the efficiency of this process by building a cache of static webpages on the server. The performance gains can be significant.
You’ll need to explore the configuration settings for the one you choose. Look for the following options:
- page caching
- browser caching
- and object caching
Progressive Web Apps (PWA)
If you have decided to build your site yourself you actually get a lot more freedom in how you design it. Most notably, you can design your site to act as a web app. The distinction between traditional web sites and web apps is often very blurry from the visitors’ point of view because we can make our websites appear and behave just like a web app! We can have interactivity, database support, and an interface that mimics an app and scales to whatever device and screen size we are using.
One of the things that defines a PWA is its ability to be used without requiring an active internet connection. In order to achieve this we make use of powerful persistent storage feature present in all modern browsers. This is a special type of cache which allows for longer term storage.
This technology is undergoing rapid evolution because of the tremendous growth in web apps but you can read more about it at Mozilla: Web Storage concepts and usage.