You'll get many and varied opinions on this topic, along with at least one exhortation to please use the search function for the info you seek. For a short answer, I have this to offer: Test ride every chance you get, on as many different types of bikes as you can. Since you're a novice you probably have no predisposition (beyond visual aesthetic, perhaps) toward any one type (road, mountain, hybrid, yadayadayada), so test them all. Enjoy!