Syncing means adding items on your computer to a device. You can use iTunes to sync the items in your iTunes library to your device, as well as photos, contacts, and other info. Automatic syncing is the quickest and easiest option: it updates your device to match your iTunes library whenever you connect the device. You can select which items are automatically synced for example, your entire library or just certain playlists.
Prevent iTunes From Automatically Syncing With Your Device
iTunes User Guide
Before syncing your content, consider using iCloud, Apple Music, or similar services to keep content from your Mac or PC in the cloud. This way, you can access your music, photos, and more on your iOS devices when you aren't near your computer. Learn more about using Apple Music or iCloud Photos instead of your computer. Sync with Finder If you're using macOS Mojave or earlier or a PC Sync with iTunes Information about products not manufactured by Apple, or independent websites not controlled or tested by Apple, is provided without recommendation or endorsement. Apple assumes no responsibility with regard to the selection, performance, or use of third-party websites or products. Apple makes no representations regarding third-party website accuracy or reliability. Contact the vendor for additional information.
If you're using macOS Mojave or earlier or a PC
Your iPod comes in handy when you want to share song ideas for a business presentation or you'd like to play music at a company party. When you connect your iPod to a computer, iTunes asks if you want to sync the device to that computer and the music library on it. If you try to sync your iPod with iTunes on a different computer, iTunes will delete your music. By backing up your music before syncing, you can prevent iTunes from deleting it. Click the "Start" button and type "folder options" in the search bar. Click "Folder Options" from the resulting search results. Click on the "View" tab, and then click "Show hidden files, folders, and drives" under Advanced Settings.
You might be surprised to learn that the Apple iPod actually wasn't the first portable device capable of playing songs downloaded as digital files from the Internet. But everyone has pretty much forgotten the Eiger Labs MPMan, which in was the first digital music player on the market [source: Van Buskirk ]. That's because the early portable devices, which early adopters used to play MP3 files that they'd copied from CDs or downloaded from file-sharing services like Napster tended to be clunky gadgets that could only store a few megabytes of music. More importantly, they took a certain amount of techno-nerditude and Web savvy to utilize.