This one's a bit difficult to answer.
According to answers.wikia there are infinite and theworldofanswers say around 3000 categories.
Maybe, a supervisor will give the answer more precisely.
Note that new categories are added frequently so there's no stable report.
There are over 11,000 categories on Answers.com.
The Suggest Link website offers many different website links to various categories one might be looking for. Some of those categories are sport, art, blogs computers and education.
There are many kind of categories that are provided by the Easy Gals website. It is most commonly known for the great recipes and plenty money saving tips.
There are several categories found at the top of the Liquorland website. The categories include specials, gift cards, cocktails, mailer, and Facebook.
There are many categories of jobs listed on the Daily Echo website. Some of these include physical jobs such as automotive and construction or service jobs such as sales or travel and leisure.
A website named TodaysBra.com lists the top selling bras in many categories.
Cleancafe is an adult website specializing in XXX rated entertainment. This a free website offering many categories of interest and is powered by third party advertising.
You can check this website http://www.tonetweet.com/ its unlimited. You can download as many as you want and its for free. You can also choose different categories that you like.
The website offers various photography categories such as portrait, landscape, wildlife, street, and macro photography.
TubeMM is an adult pornographic website, which mirrors many adult films from other tube websites. It includes many categories of films, including "Drunk", "Reality" and "Webcam".
Burning Camel is a pornographic website featuring mostly amateur porn. They have many categories and sub-sections depending on your individual requirements.
Categories can be deleted, but only by Answers employees not by it's regular users or Supervisors.