iTunes enhances Apple's media software in a number of ways. It is used mostly for managing audio and video content for your PC. When you synchronize your iPod with Apple's iTunes software, it will delete all the music content in your iPod. To resolve this, connect your iPod to your system and click on the iPod icon. Select 'manually manage music' and create a playlist by adding the songs you want in your iPod. Then click Music. Select the created playlist and click on Auto fill, which adds all the songs to your iPod without deleting the other songs in your iPod.