By Umar Syed | @UmarSyed

Tumblr is a microblogging site that allows users to easily share text, photos, quotes, links, music, and videos from a browser, phone, desktop or email. David Karp founded Tumblr in 2007, and with the recent rise in popularity the service now has over 12 million blogs and 2.7 billion posts with an average user creating 14 posts a month.

While often compared to traditional blogging platforms like Blogger and Wordpress, Tumblr stands in it’s own category. Where Tumblr differentiates itself from its competitors is with its customization options and its Twitter-esque ‘Follow’ and ‘Reblog’ features. To reblog is similar to a retweet on Twitter, which gets your content out to a larger audience by others reposting your blog post to their followers, thus allowing posts to go viral and create Internet memes. The ‘Follow’ feature gives Tumblr a sub-community feel to it where you can interact with those you follow.

Like other blogging services, Tumblr gives users the option to create a custom domain and uses Google Analytics to provide stats on blog traffic and which posts are more popular than others. Tumblr blogs are highly customizable; the service provides users with hundreds of themes to choose from with in-depth appearance personalization options and the ability to create your own theme using HTML.  Another feature Tumblr has is ‘Photosets’, which enables users to upload a collection of photos and post it as one Tumblr post. The photoset can display the pictures in a slide show format or in a grid to be clicked individually.

Aside from personal use, many brands are starting to optimize Tumblr for business use. Brands are providing discounts, rewards, a look behind the scenes, thought leadership and more through their Tumblrs. Even further, traditional news media outlets have joined as well. Mashable lists Newsweek, The New York Times and The Atlantic as newspapers adjusting well to the trend.

For a fun list of other successful Tumblr blogs, check out by “The 60 Best New Tumblr Blogs of 2010” by BuzzFeed.