What is a WordPress plugin? A plugin is a tool used in self-hosted WordPress to extend its functionality and add new features. Similar to installing an app on your phone, WordPress plugins are apps that integrate and run on top of WordPress. This allows you to make almost any type of website with WordPress, not just blogs.
In a non-technical way, a WordPress plugin is a piece of software that can be installed on your WordPress installation that extends its capabilities by adding new features and functionality without writing any code.
At its core, a WordPress plugin is a folder made up of files written in the PHP programming language, which includes other assets such as JavaScript, HTML, CSS, and image files.
The free and open-source WordPress software was created in a way that lets other developers add their own code on top of it. By using hooks from the WordPress plugin API, developers can add and modify existing WordPress functionality.
Developers can also store data in the WordPress database, create custom content types, taxonomies, and custom fields.
The WordPress plugin directory has thousands of free and freemium plugins available for anyone to use. Freemium plugins are released free with limited features with upgrade options to add more. Additionally, there are also premium plugins developed by third-party companies and developers.

Site administrators can install and uninstall plugins from the admin area. You can also upload them and install them manually using an FTP client.
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