WordPress Plugins are also known as add-ons or extensions. They are software scripts that add functions and events to your website. They cover the gamut from up-to-date weather reports to simple organization of your posts and categories.
Plugins are designed by volunteer contributors and enthusiasts who like challenges and problem solving. They are usually fairly simple to install through the WordPress Admin Plugin Screen, just follow the instructions provided by the plugin author. Remember, these are free and non-essential.
If you have any problems with plugins, contact the plugin author’s website or plugin source first, then search the Internet for help with that specific plugin, and if you haven’t found a solution, then visit the WordPress forums for more help.