WordPress Plugin: A WordPress Plugin is a program, or a set of one or more functions, written in the PHP scripting language, that adds a specific set of features or services to the WordPress weblog, which can be seamlessly integrated with the weblog using access points and methods provided by the WordPress Plugin Application Program Interface (API).

There are tons of WordPress plugins out there. Some of them can be really helpful, while others are just a waste of disk space. Let’s take a look at 32 really useful WordPress plugins and why you should use them.

1. Google XML Sitemaps

2. All in One SEO Pack

3. WordPress Database Backup

4. Contact Form 7

5. Google Analytics for WordPress

6. PXS Mail Form

7. WP e-Commerce

8. ShareThis

9. Redirection

10. Yet Another Related Posts Plugin

11. Sidebar Widgets

12. Get Recent Comments

13. Akismet

14. WP lightbox 2

15. Ultimate Tag Warrior 3

16. My Page Order

17. Adsense-Deluxe

18. Search Regex Plugin

19. Tweetmeme

20. WP-SpamFree Anti-Spam

21. Theme Authenticity Checker

22. List Category Posts

23. Expanding Text Plugin

24. Actionable

25. Advanced Tagline

26. Sodahead Polls

27. Minimum Comment Length

28. Blogging Tips

29. Gravatar Recent Comments

30. WordPress Super Cache

31. WPtouch: WordPress on iPhone, iPod & Android

32. Blog Alerts