The iPod is a portable media player introduced by Apple in 2001. Prior to the iPod, the Sony Walkman was the most popular music player for anyone who wanted to listen to music on the go. The Walkman was somewhat bulky, however, and the musical selection was limited to however many 90-minute cassettes its owner could stuff into a fanny pack.
The iPod shrunk both the musical format and the device used to play songs to a single object about the size of a credit card. Some models, such as the 160-gigabyte iPod Classic, can store 50 days’ worth of music. PC World magazine said the iPod had “irrevocably altered the landscape for portable audio players,” and indeed it so outpaced sales of the cassette-playing Walkman the latter simply couldn’t compete. The Walkman was discontinued in October 2010.