Hard drive models have large storage capacities and are great for storing all your music without the hassle of having dozens of CDs around. However, MP3 players with hard drive units tend to be bigger in size, and they need to be handheld while you jog. Storage sizes may vary from 512MB (about 120 songs) to 60GB (about 15,000 songs).

Flash-based models are small and sleek and usually fit in your pocket. They are great for active users who are always on the move. However, they have low storage capacity (less than a few dozen songs). To solve this problem, you can choose to add a costly memory card whose capacity vary from 32MB (about 8 songs) to 4GB (about 1000 songs).