Regardless of what kind of business is involved you will need a company name. Many small business owners use their own names like "John Doe Messenger Service.” That is perfectly alright but what if you want to use a name with more marketing appeal like "Flash Messenger Service"?
First check to be sure that no one else in your area of operations and industry is already using a similar name. On the example given, there would be a problem if someone was already operating "Flash Bicycle Delivery" because customers could be confused. You can do your research by checking telephone directories in your area, doing a Google search, and searching the online database maintained by the Illinois Secretary of State. Or you can contact the Secretary of State by phone at (800) 252-8980. The Secretary of State will not allow you to form a corporation or LLC if the name you wish to use is the same as the name of an existing corporation or LLC.
If you plan to do business on a nationwide basis, you should also check the trademark database maintained by the U.S. Patent and Trademark Office for any trademark that is confusingly similar to the company name and trademark that you wish to use.