A WordPress plugin is a piece of software that extends the functionality of a WordPress website. It is essentially a package of code that can be installed and activated on a WordPress site to add new features, functions, or capabilities to the website without modifying the core WordPress software.

Plugins can be used to enhance various aspects of a WordPress site, such as adding new features, improving performance, enhancing security, optimizing SEO, creating contact forms, integrating with social media, managing backups, and much more. WordPress plugins are typically developed by third-party developers and are available in the WordPress Plugin Directory, which is a repository of thousands of plugins that can be installed and used by WordPress website owners.

Plugins can be easily installed and activated from the WordPress admin dashboard, and many of them offer settings and customization options that can be configured to suit the needs of a specific website. Plugins provide a flexible and modular way to add functionality to a WordPress site without having to modify the underlying WordPress core code, making them a popular and powerful tool for extending the capabilities of WordPress websites.

Here are 10 highly recommended WordPress plugins for websites:

1. Yoast SEO: A comprehensive plugin for search engine optimization (SEO) that helps you optimize your website’s content, meta tags, XML sitemaps, and more to improve your site’s visibility in search results.
2. WooCommerce: A powerful e-commerce plugin that allows you to create and manage an online store, including product listings, shopping carts, payment gateways, and more.
3. Jetpack: A multifunctional plugin that offers features such as website performance optimization, security scanning, social media integration, and content management tools, among others.
4. Contact Form 7: A popular plugin for creating and managing contact forms on your website, with customization options and support for multiple contact forms.
5. W3 Total Cache: A caching plugin that helps improve website performance by storing static HTML files of your web pages, reducing load times and improving user experience.
6. Akismet: A powerful anti-spam plugin that helps filter out spam comments on your website, keeping your comments section clean and free from unwanted content.
7. UpdraftPlus: A reliable plugin for website backups and restores, allowing you to easily create scheduled backups of your website’s files and database, and restore them when needed.
8. Wordfence: A comprehensive security plugin that offers firewall protection, malware scanning, login security, and other security features to protect your website from malicious attacks.
9. Smush: An image optimization plugin that automatically compresses and resizes images on your website to improve loading times and reduce bandwidth usage.
10. Elementor: A popular drag-and-drop page builder plugin that allows you to create custom web pages with ease, offering a wide range of design elements and customization options.

Please note that the popularity and usefulness of WordPress plugins may vary over time, so it’s always recommended to research and review the latest plugins and their reviews before installing them on your website