iTunes is an online music store that is run by Apple. iTunes must be downloaded to your computer in order for you to use it, but the download is free, quick, and easy. Simply visit www.apple.com, click on iPod + iTunes, and then click on Free Download. iTunes will show up on your computer menu as a CD icon with green musical notes on it. Double click the icon to open iTunes, and you're ready to go.
iTunes allows you to download songs one at a time for $0.99 apiece, or you can download an entire album. This is great because if you hear one song you like, you can buy it without having to buy the whole album. When you purchase songs, they go into your library. When you click on "library," it will list all of the songs that you own. At the top of the screen you can see the columns labeled Name, Time, Artist, Album, Genre, My Rating, etc. Clicking on any of these words will sort the songs by that medium. So if you click on Name, your songs will be sorted alphabetically by name. If you click on Artist, they will be sorted alphabetically by artist. This helps you find the song you're looking for more easily and quickly.