If you have used a computer, you have dealt with cache.
Perhaps you’ve heard that “clearing the cache” can help you speed up your browser. Perhaps you’ve then felt it was contradictory that cache was supposed to speed up your browsing experience.
So what exactly is cache and for what purpose do we use it?
In this article, you will find out:
- What is cache and why we use it
- What is server-side cache
- What is client-side cache
- WordPress-specific cache plugins
- How to optimize your website for speed
What is Cache?
The concept of cache is simple: it is a component in computing that stores temporary data so that it can be reused when necessary and therefore improve performance speed.
For example, a web browser cache will save a website’s static content.
Since loading the content from cache is faster than downloading it every time you visit a website, your loading time improves dramatically.
As a WordPress user, you should differentiate between two types of caching for your website: server-side and client-side.
Server Side Caching
Server-side caching is exactly what you might think it is – caching which uses the server as storage, as opposed to using your local machine.
There are several types of server-side caching, some of which are:
HTML stands for Hypertext Markup Language and is also a file extension. An HTML file will contain your website’s code and embedded content such as custom CSS.
Page caching allows HTML files to be saved in order to improve website loading time.
Database caching allows for faster query processing, especially when accessing large databases. Most websites these days have an increasing amount of data stored, such as websites that feature stores and therefore lots of user information.
Large databases can be a resource hog so it is especially useful to provide in-memory access to the database’s most frequently used queries.
There are several object caching solutions available, some of the most popular ones being Redis (an open source, in-memory database) and Memcached (a multithreaded in-memory cache). Database caching is a subset of object caching – a query is first made to a database such as MySQL after which the result gets saved in an intermediary such as Redis.
The next time the query is made, it no longer has to be made to the database and is instead loaded out of cache.
Opcode or OPcache
A part of your website’s code is the PHP script, which needs to be compiled at runtime. Instead of compiling it each time you visit a website, opcode caching will save the compiled script to the server cache, eliminating the need to compile the code every time and speeding up the loading process considerably.
A content delivery network is a network of proxy servers which minimizes website loading time by loading content from a server which is physically closer to the user.
A CDN will cache images, videos or entire webpages in order to provide maximum speed and availability of content to the requesting user.
As opposed to server-side caching, its client-side equivalent means the data is stored on your computer locally.
This is probably the type of cache you are most familiar with – the browser cache.
Also known as the HTTP cache, it stores any downloaded website content directly on your local machine.
The next time you load the website, your browser will first access its cache to see if a saved version of the website exists.
If it does, no additional requests need to be sent to the server, which saves on both loading time and bandwidth.
WordPress Plugins for Managed Cache
This popular plugin caches HTML files in order to bypass loading from PHP code.
It offers three modes; WP-Cache, expert and simple so that everyone ranging from an experienced user to a new one can enjoy the speed benefits.
While similar to WP Super Cache, the W3 Total Cache plugin emphasises optimizing SEO rankings.
As most websites are ranked for speed when it comes to SEO recommendations, this plugin boasts a 10x improvement in website loading time which in turn leads to higher ranking of your website on web searches.
Other than caching your data, WP-Optimize also cites it “cleans the database”.
In the context of this plugin, cleaning the database means periodically removing files that are no longer necessary, such as spam comments and other stale data.
WP-Optimize also offers a wide range of options for scheduling which might appeal to users who like to specify the number of cleanups needed.
LiteSpeed Cache presents itself as not only a caching plugin, but an all-around acceleration service.
Other than caching, it also deals with minifying code (streamlining code and stripping it of all unecessary data) and lazy loading (showing only one part of your website to the user for improved speed, especially useful for mobile devices).
It supports object-caching services such as Redis and also offers support for multiple CDNs.
Optimizing Your Website
As you can see, caching is extremely important in order to improve website loading speed.
However, website speed is best optimized by using multiple strategies, some of which are:
Using GZip to Compress Files
GZip is the name of a software application and its associated file format. Its intended use is for file compression and decompression and it’s the most widely used method for compressing website files.
GZip compresses your website’s HTML file and any stylesheets or scripts you might have into a single streamlined file which can then be served to the client’s browser.
All modern browsers support GZip compression.
As previously mentioned above, minifying code is the act of removing all data which is unnecessary for the code to be properly executed.
This includes any blank spaces, new line characters and comments which might be a part of your code.
Like the name suggests, minifying your CSS and JS code will make it smaller and therefore easier to transmit.
Other than saving bandwidth, making your code more efficient improves overall website performance.
Using a Content Delivery Network
Using a content delivery network or CDN is a popular solution for improving delivery speed.
The CDN stores static content on a server physically closest to the requesting client, which minimizes loading and delivery time.
There are many CDN solutions available, including the very popular CloudFlare.
Improve page speed with Hostdedi Edge, our purpose-built Content Delivery Network. It is integrated into our platforms for easy use without a ton of configuration complexity.
Optimizing Images Using Lazyload
Since most images these days are high quality and therefore large in size, it might be useful to utilize an image optimization solution. For example, the Smush plugin compresses images with the goal of reducing size but keeping the quality high.
It also offers the ability to “lazy load” your website, which is a service that loads only the part of your website the user is currently viewing.
This greatly improves speed on mobile devices. Since the screens cannot show the entire webpage at once, loading content as the user accesses it allows for greater delivery speed.
It goes without saying that staying updated is important. Plugins and themes are always being actively developed so it is best to keep them updated at all times in order to ensure compatibility and optimal performance.
Get Built-In Caching With Hostdedi
In combination with other methods, using a caching solution such as a plugin can greatly improve website performance and therefore customer satisfaction.
Caching comes in various shapes and sizes and is an integral part of not only computing, but also modern hosting.
Fully managed WordPress hosting by Hostdedi comes with built-in caching for ultra-fast loading, plus a CDN with 22 locations. All hosting plans also include:
- Premium tools such as Visual Compare, WP Merge, iThemes Security Pro, and more.
- Image compression to lower browser load times.
- Always-on security monitoring & support from WordPress experts 24/7/365.
- No overage fees, traffic limits, or metered pageviews.
Check out managed WordPress hosting, or experience it for yourself with a free trial.