There are seven category types for the Articles you can write on Experts Exchange.
You can change the Article category via the dropdown at the top of the Write Your Article page, where the default category is set to General Article.
Remember, Articles on EE should generally be between 300-600 words (feel free to write longer) and include your original thoughts along with links to any source material.
Here are the different Article categories and when you should use them:

General
Articles that don't exactly fall into the other six categories should be published as General Articles. These, like all articles, should be at least 300 words to be considered for points. Code snippets, screenshots and other attachments are encouraged to help readers grasp what you're writing about.  

FAQs
Like most FAQs, these answer common questions related to a common IT or tech-related problems. We have an FAQ, for example, on writing articles for EE.
http://www.experts-exchange.com/articles/Community_Support/Article_Tips/Articles-FAQs.html

Tutorials
These are step-by-step instructions, on how to install Windows XP for example. Be sure to review the Article Formatting Tips on the Write Your Article Page to learn how to add steps to your article.

Reviews
These should be objective reviews of tech-related items such as software or hardware. Please try to include a photo and model number of the item you are reviewing along with a link to the manufacturer's site if possible. Include a brief product summary, your likes and dislikes, followed by a conclusion and personal rating to help round out the review.  

Best Practices
These articles are more like guidelines or a 101 document. An example is an SEO best practices guide.

Tips and Tricks
These articles offer up tidbits of useful knowledge to help make your tech life a little easier. Remember, to be considered for points, your article should be at least 300 words. So if you need to include 4 or 5 tips about a related subject, please do so.

Resources
These are articles you feel would be resourceful and worth bookmarking for others. Examples could be a list of links to useful/reputable sites that may help you find a solution to a common problem, with your descriptions about what makes each site helpful. Top 10 lists, where you elaborate on each item. Like with all articles, make sure these articles are at least 300 words and include your original thoughts along with links to all source material.