WordPress plugins expand the capabilities of your wordpress website far beyond the original installation.

They are used extensively to enhance the look and capabilities with fancy image and video inserts into posts and wordpress pages. Others for security reasons to keep your website as hacker safe as possible.

The must haves include SEO plugins to enhance your search engine rankings and position in results.

Those looking to add a little money making capabilities into their website can install adsense plugins.

Sick of website email spam, add on captcha code to make sure whoever is filling in your contact form is actually a real live person.

If you have a need for something extra, you can guess someone else does too and the plugin has already been invented. This is open source programs at their best, a huge community of people making and sharing extensions.