Here are some of the most popular WordPress plugins:

1. Yoast SEO: Yoast SEO is a plugin used to optimize websites for search engines. It helps users to improve their website’s SEO by providing suggestions and tools to improve on-page optimization.
2. Jetpack: Jetpack is a powerful plugin with many features, including site security, traffic growth, and performance optimization. It can also help with social media sharing, spam filtering, and backups.
3. Contact Form 7: Contact Form 7 is a popular plugin for creating contact forms on a website. It’s easy to use and highly customizable.
4. WooCommerce: WooCommerce is a plugin used to create online stores on WordPress. It provides a lot of flexibility, with various extensions and integrations available for customizing the online store.
5. WPForms: WPForms is a drag-and-drop form builder plugin that makes it easy to create various types of forms, including contact forms, surveys, and order forms.
6. Smush: Smush is a plugin that optimizes images on a website by compressing them. This helps to reduce the website’s loading time and improve the website’s overall performance.
7. W3 Total Cache: W3 Total Cache is a plugin used to improve website performance by caching content, optimizing images, and compressing pages. This can help to reduce the website’s loading time and improve user experience.
8. Akismet: Akismet is a plugin used to protect websites from spam comments. It filters out spam comments and ensures that genuine comments are not mistakenly marked as spam.
9. MonsterInsights: MonsterInsights is a plugin used to integrate Google Analytics into WordPress. This allows users to track website traffic and get insights into visitor behavior.
10. Elementor: Elementor is a popular page builder plugin used to create custom page layouts and designs without coding. It’s highly customizable, with many templates and widgets available.