How to See if Your iPod or iPhone Has the Latest Software
Your iPod (or iPhone) works best with the latest or newest software installed. iTunes tells you whether your iPod or iPhone contains the newest software. Connect the iPod or iPhone to your computer and select it in the iTunes Source pane (in the Devices section). The iPod or iPhone summary page appears to the right of the Source pane, and the Version section of the page tells you whether your iPod or iPhone software is up to date and when iTunes will check for new software. (See the following figure.)
You can check for new software at any time by clicking the Check for Update button on the Summary page.
Some iPod models need to be disconnected from the computer temporarily and connected to a power source to finish the process of updating the software. Follow the instructions to disconnect your iPod and connect it to an AC power adapter, if required.