Choosing to buy the right MP3 player isn't that difficult, but one player does not fit all. People will want different things from their players. MP3 CD players represent the best value: Most retail for less than $200, and additional blank discs are cheap.

* Think about how you'll use the player. Joggers will almost certainly want a lightweight, flash-memory-based device, since hard drives don't react well to the shock of bouncing around all the time; audio aficionados who want lots of music at their fingertips should keep their eyes on the highest-capacity hard-drive models.

* Try your favorite before taking it home. Make sure you can use the on-screen display to navigate to a specific song, and ask a clerk to show you how to transfer music to the device, if possible. Always bring your own set of headphones to listen to the sound quality of each unit you're interested in. If you plan to test CD-based MP3 players, bring your own disc.

* Get the largest-capacity device you can afford. Whether you buy a flash- or hard-drive-based MP3 player, make sure to choose a model with the largest storage capacity possible. Even if you don't think you'll need it now, you will probably be happy to have it later.

* Pay close attention to the user interface. The simplest-to-use MP3 players use a Windows Explorer-like file and folder interface to organize music on the player. While some players require you to use their software to pick the play order before loading music files, other players let you rearrange the songs once the music is in the player.

* Mind your power options. While some portable players use replaceable alkaline batteries, many feature a built-in rechargeable battery that cannot be easily removed. While these devices can keep going for tens of hours, if you're not going to be somewhere near a power outlet or a computer with a USB port, you might find yourself out of juice with no way to charge the player.

* Check the prices for extra storage. If you're considering a player that uses one of the major memory card formats (Secure Digital, SmartMedia, MultiMediaCard, or Memory Stick) to store music files, factor the price for an extra or replacement memory card into the cost of the player.

* Look for wide file format support. While this isn't a necessity, players that support music files in the MP3, WMA (Windows Media Audio), and OGG formats give you more listening options than players that support just one or two of those formats.

* Consider a player with an FM tuner. This feature isn't essential, but it's a nice addition--especially if you grow tired of your own music.

* Do you need a carrying case? The more expensive and more fragile the player (hard-drive devices are the most delicate), the more likely you'll want a custom-fitted case to protect it. If you plan to carry your player with you wherever you go, consider investing in both a fitted cover and a rugged carrying case that can also hold headphones, a USB cable, and/or spare batteries.

* Shop around, online and offline. MP3 players are widely available in almost every consumer electronics outlet, and their prices fluctuate.