A WordPress plugin is a program or set of functions, written in PHP, that adds specific features or services to a WordPress website, which can be integrated into the site with methods provided by the WordPress API. A plugin can add additional functionality, or modify existing WordPress features.

Setting Up A WordPress Plugin

The first step in creating a plugin assign a unique name to your plugin. It is wise to choose a name that somewhat describes what the Plugin does. The name can be multiple words.

The next step is to create a PHP file with a filename similar to your chosen Plugin name. For instance, if your Plugin is called “Homepage Banner Manager”, you might call your PHP file home-banner-manager.php. Again, try to choose a unique name so that plugin files are not being overwritten if two different plugins have the same name.

You can split your Plugin into multiple files. However, the plugin must have at least one PHP file, but it can also include JavaScript, CSS, image files, and more. If there are multiple files, once again, pick a unique name for a file directory and store all your plugin files in this directory.

The top of your Plugin’s main PHP file must contain a standard Plugin information header. This header lets WordPress recognize that your plugin exists and adds it to the main plugin management screen so it can be activated. The header might look something like this:

Plugin Name: Name Of The Plugin
Description: A brief description of the Plugin.
Version: The Plugin's Version Number, e.g.: 1.0
Author: Name Of The Plugin Author

Using WordPress Plugin Hooks and Actions

At various times while WordPress is running, WordPress checks to see if any Plugins have functions that registered to run at that time, and if so, the functions, or actions, associated with that hook are run.

Storing Plugin Data

There are a few different methods for saving Plugin data in the database:

1. WordPress “Options”: This method is useful for storing small amounts of relatively static pieces of data such as Plugin settings. Option values can be strings, arrays, or PHP objects. Option names must be unique strings so that they do not conflict with other WordPress components.
2. Post Meta: This method uses data from a page’s or post’s custom fields.
3. Custom Taxonomy: This method is useful for classifying posts or other objects such as users.
4. Custom Database Tables: This method is used for data not associated with individual posts or pages.

By: Sarah