Yoast SEO
Yoast SEO is one of the most popular WordPress plugins of all time. Yoast SEO is an awesome plugin which guides you all the way to create better content and improve your ranking on search results
Akismet
The plugin provides a status history for each comment so that you can learn which comments were found spammy by Akismet or the moderator. Moderators also can view the number of approved comments for each user, see the URLs in the comment body and remove the suspicious links.
WP Smush
Yes, you can compress and optimize the images without reducing the quality of the images using WP Smush plugin. It optimizes all of your image files in JPEG, GIF and PNG formats using advanced compression techniques and saves lots of storage space
W3 Total Cache
To enable caching in WordPress, you can use WordPress caching plugins. Caching plugins will cache your posts and pages as static HTML files which are served to the users. This reduces page loading time drastically and helps to optimize the overall site performance.
Jetpack
Jetpack takes care of your site security, website performance, traffic growth, image optimization, website appearance and a lot more.
