WordPress plugins can help you solve a problem, like protect your blog from hackers and spammers. Plugins can also help you manage your site like adding a calendar, a photo gallery, a video, or slide show. They can perform backups at regular intervals and do a million and one other wonderful things.
Once you learn how to install WP plugins to your blog, you will learn that plugins have infinite possibilities.
You don’t have to install a WordPress plugin on your blog, but you should look at some of them and see if they will help you achieve your blogging goals.