However, what you see there is only the end product.
In the background, much of any given WordPress page is actually constructed from PHP functions and database queries. These get interpreted by the browser who then spits out the page in a viewable form.
While CSS works well to make superficial changes (colors, sizes, etc.), if you want to make bigger, structural alterations, you will need to deal with the source code.
One possibility to do so is to locate the respective lines of code in the core files and replace them with your own. It’s a method that does (unarguably) work and that some people continue to use.
However, the disadvantage of this practice is that with the next WordPress update all your customizations will vanish. The core files get overwritten and — poof — all your changes are gone.
Plus, not updating isn’t a good idea, since it poses a serious security risk. So, what to do?
Thankfully, there is a way to change the code in WordPress without actually changing it. Sounds impossible? Well, let me introduce you to WordPress hooks.
What are WordPress hooks?
Hooks are an incredibly powerful tool. Knowing how to leverage them is one of the most important concepts for both plugin and theme development.
Even if you are not a developer and just looking for a more elegant and efficient way to make changes to your site, you can still benefit from learning about WordPress hooks.
For example, hooks are widely used in theme frameworks such as Genesis to allow for easier theme customizations. But don’t let that scare you off.
So what are they?
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A Quick (and in-Depth) Guide to WordPress Hooks »