Credit cards are increasingly becoming the most popular way for small businesses to conduct their businesses, with 59% of respondents to a 2009 SBA survey saying they favored using a credit card to fund business purchases.

When it comes to cards though, it’s handy to know why you’re getting one to use in your business, and what you should be shopping around for. Entrepreneur.com has a handy primer on business credit card use, covering such important matters as fees and interest rates:

One of the most important considerations is how much a credit card will cost you. There are two main fees (not counting late charges and the like, which, hopefully, you won’t have): annual fees and interest rates.

Annual fees are a once-a-year charge you’ll have to pay for the honor of carrying a credit card. Very few card issuers offer no-fee cards for businesses, and they’re usually offered only to businesses with the best credit histories. Fees vary, and many come along with benefits, such as rewards programs. (More on that later.)

Then there are interest rates, which have been on the rise for consumers and business accounts alike. According to CreditCards.com, the average business credit card had an interest rate of 11.31 percent (as of the week of Feb. 3, 2010). That can get pretty expensive if you carry a balance for a long period, especially if you plan to use the card for start-up business costs.

Get the whole scoop on business credit cards here.