WordPress is a powerful Content Management System that can be used to build a
website, a blog or both. It is flexible for use, and the level of customization
is high.Plugins extend the functionality of WordPress in many different ways. Plugins
are so popular nowadays because of its multiple usages. Below please find wide
usages of WordPress plugins;
For enhanced advertising management, ‘Advertising Manager’ ,which is user-friendly with its all-in-one solution to support advertising no
matter for any network. This plugin can automatically recognizes almost all the
ad networks available online whileMax Banner Ads allows users to rotate several banners in a single spot or multiple spots, and
you can choose from several locations, including your header, sidebar, footer,
or even within your posts.
For enhanced comment Management, MyAvatars, is a very useful plug-ins as they allow readers to associate pictures with
the comments themselves. Providing a visual cue such as an avatar, allows the
users to easily follow who is saying what, and who has feedback.Subscribe to comments is one of the most important plug-ins that every blog should offer. This plug-in will automatically place a subscription box in your comments form and allow readers to receive e-mail notifications each time a follow up comment is left on your site. 
As an aid to the admin tools, WP-DM Manager, is designed to add a ‘Database tab’to your dashboard.  Management options range from backing up, restoring your
backups, optimizing and repairing your database ; whileMobilePress plug-in, is a WordPress plug-in that will render your WordPress blog on mobile handsets, with the ability to use customized themes. The plug-in also allows specific themes for specific devices / mobile browsers, such as iPhone, Opera Mini or Windows CE Mobile.
For Blog Affiliates, Auction Thumb, especially beneficial for people that maintain a WordPress blog which discusses products that convert
well on eBay. Auction Thumbs allows authorized WordPress user to fully
integrate eBay’s affiliate program into their blog. With this plug-in, you can easily display
your eBay ads in any desired post / blog.WP Affiliate pro, though not free, but many found this to be worth it as it allows one to manage everything on
your WordPress dashboard.
The ‘All in One’ Video Pack having video enhancement feature which can be used to Upload and record from webcam, plus to import all rich-media directly to your blog post; allow edit and remix videos using Kaltura’s online full-featured video editor; and to import all rich media from other sites and social networks, such as YouTube, MySpace, Flickr and Jamendo.
The Ultimate SEO “All in one SEO package Plug-In” is a powerful tool to set homepage meta information and automatically
generate custom meta information for any individual posts.  One can control everything from the Options panel. As for Permalink Redirect , you are using the most current version of this plug-in, you’ll see that it is able to manage several different aspects of your WordPress blog and manage to redirect any alternate URL’s to the URLs of your choosing.  
In a nut shell, wordpress Plug-ins has increasingly become a necessity now for
every bloggers as they are helper, and is a great tool to enhance the
performance and traffic of blogs and websites, as well as to make sure that it
is SPAM-protected at anyone time!

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