Regularly backups your website so you free of worry about your site corruption.
Very easy to create forums which looks native to your website.
Tightens your website security though depends on your website hosting company not all options are enforcing.
Free CDN for your site again your website hosting site support is needed to enable it.
Professional looking commenting system for your site, has community and some other nice feature as well.
Needless to say anything about this.
Helps adding Google Analytics to your site in easy way.
Generate site maps which are easy to be submitted in Google webmaster and bing.
10. Gravatar Favicon
An avataar system to be used for any site integrating nicely into wordpress.
Makes it super easy to make your site translated on the fly to cater to a larger audience.
Many useful options such as site stats, mobile themes, wordpress.com integration etc. Very useful.
As the name says handy newsletter creation.
14. PayPal Donations
Easy to use donation plugin to get support for your siite.
15. Scripts Gzip
Compress your scripts to fasten your website.
Adds lots of social networking site sharing to your posts.
17. Ultimate TinyMCE
Ultimate editor to create posts if not wrong used by wordpress.com as well.
18. W3 Total Cache
Lot of caching options to make your website faster. Again depends on your website.
Integrates antivirus and firewall in your website.
Enable gzip compression to make your website load faster.
Import your posts from other worpress site.
Save your site from being tagged as ping spammer.
23. WordPress SEO
Search engine optimization tools tightly integrated into your site.
Automated posting into your website.
Optimize your database.
A better menu navigation system.
Highlight your code snippets into colorful coding.
28. WP Smush.it
High images are bottleneck into site performance make it faster with this plugin.
Make your website ready for touch screen based devices like iPhone etc.
Automatically creates related posts entries for your posts.
Adds how many times a post has been viewed.
I’ve given very short intros of these plugins however you can click on links and see the details.
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