Welcome to the NZRT Wiki Podcast. Today we’re looking at 📚 WordPress Functions Cheatsheet.

If you’ve ever built a WordPress plugin or theme, you know how quickly you end up hunting through documentation just to remember the exact name of a function. This cheatsheet is your quick reference for the most common WordPress PHP functions — the ones you’ll reach for again and again. Let’s walk through them group by group.

We’ll start with posts, because that’s the heart of almost everything in WordPress. The first function lets you fetch multiple posts at once by passing in an array of arguments — things like post type, category, number of results, and ordering. You get back an array of post objects to loop through. If you only need one specific post and you already know its ID, there’s a simpler function that takes just that ID and hands you back a single post object. From there, if you’re inside the Loop — WordPress’s standard way of rendering content — you can call a function that just outputs the post title directly to the page. Same idea for the content. Another function handles creating or updating posts: you pass it an array of data describing the post, and WordPress takes care of inserting it into the database. And when you need to remove a post entirely, you pass its ID to the delete function and it’s gone.

Next up are hooks, which are one of the most powerful concepts in WordPress. Think of hooks as event listeners. There are two flavours: actions and filters. An action hook lets you attach your own function to a specific moment in WordPress’s execution — for example, right after a post is saved, or when the page header loads. You register your callback with the action hook name, and WordPress calls it at the right time. Filters are similar, but instead of just running code at a moment, they let you intercept a value, modify it, and pass it back. So if WordPress is about to output a piece of text, a filter lets you jump in and change what gets displayed. On the firing side, there are two corresponding functions — one that triggers an action hook so all attached callbacks run, and one that runs a value through all attached filters and returns the result. Understanding this four-function pattern — add action, add filter, do action, apply filters — gives you enormous flexibility in both plugins and themes.

Now let’s talk about the database layer. WordPress has its own options system for storing simple key-value settings, and there are two functions for it. One retrieves a stored option by name, and the other saves or updates a value against that name. These are perfect for plugin settings. For anything more complex, WordPress gives you access to a global database object. You can pass a raw SQL query string to it and execute it directly — useful for custom tables or complex queries that the higher-level functions don’t cover. Just be careful to sanitise your inputs properly when going this route.

Finally, we have user functions. If you need to know who’s currently logged in, there’s a function that returns their user ID — simple as that. Once you have that context, you’ll often want to check whether they’re allowed to do something before you let them. There’s a function for that too: you pass it a capability string — things like “edit posts” or “manage options” — and it returns true or false based on the current user’s role and permissions. This is the right way to gate functionality in WordPress rather than checking roles directly. And if you need to pull extra data stored against a user — things beyond their name and email, like custom profile fields — there’s a function that takes the user ID and a meta key and gives you back that stored value.

Tying it all together, this cheatsheet maps to three broader areas you’ll want to explore in the related notes: Plugin Development, Theme Development, and Hooks and Filters. The functions here are the building blocks that appear across all three. Whether you’re registering a custom post type, building a settings page, or intercepting content before it renders, you’ll almost certainly be combining functions from these four groups.

Keep this reference handy, and you’ll spend a lot less time digging through the WordPress developer docs and a lot more time actually building.

That’s it for this episode of the NZRT Wiki Podcast. Thanks for listening.