Jackson Hewitt Inc. is one of the largest full-service tax preparation companies in the United States. Located in Baltimore, Md., the company specializes in individual federal and state income tax return preparation. It also offers an online tax preparation product at www.jacksonhewittonline.com. Through the tax help center, the tax preparation firm helps its clients to understand complex tax laws. Additionally, Jackson Hewitt Inc. offers a series of income tax preparation courses through online as well as traditional classrooms.