What are your favorite plugins in WordPress?

Plugins are useful if you want to extend the functionality of a WordPress site. The plugin you use on your website can be the difference between running a Wordclass website and another website. With so many connectors to choose from, that's my favorite.
1. Jetpack with automatic
2. Yoast SEO plugging
3. Optin Monster
4. Entire W3 cache
5. Wordfence security plugin
6. Secure your buddy
Let me know what your favorite WordPress plugin is below.