Again, you can definately go to Wordpress and get yourself a free blog. The site is marvelous and you will truly find yourself a professional looking blog. While the don't charge you a dime, your capabilities will be limited in the sense of monetizing it as Rajanrayhan has stated.
From a business perspective you may want to have it self-hosted for more freedom and personalization. I have been using a host of choice where not only do I get to choose a personalized domain for my Wordpress blog, but I am able to monetize it. You're able to try it out for free, and even if you decide to keep it the cost is very affordable. If you'd like to know more simply contact me via my Hub profile.