There are several MP3 players available for Macintosh. These instructions cover installation of iTunes, an MP3 player developed by Apple. The instructions are for computers running OS X.

1. Check to see if iTunes is available via Apple's Software Update service. Under the Apple menu, select "System Preferences." Locate the "Software Update" control panel and click on its icon. Click the "Check Now" button to download a list of available software.

2. If iTunes appears in the list of updates available for your computer, click the checkbox next to it and click "Install Updates Now." Software Update will download and install iTunes.

3. If iTunes does not appear in the list of updates available for your computer, visit the iTunes web site at http://www.apple.com/itunes/.

4. Click "Download now" and fill out the registration form. When you submit the registration form, the iTunes Installer will begin downloading.

5. When the download is finished (check the "Downloads" or "Downloads Queue" window in your browser) a folder containing the iTunes installer will open in the Finder. (If the folder does not automatically open, locate the file downloaded by your browser and double-click it.)

6. Double-click the iTunesX.mpkg file in the folder that just opened (where X is the current version of iTunes) to start the iTunes installer. Enter an administrator password when requested and follow the prompts to finish installation of iTunes.

7. Test your new software.

Visit the iTunes support web site at http://www.apple.com/support/itunes/ for more instructions, or if you have difficulty installing iTunes.