How do I know if my cable supports data transfer?

1. Check the product packaging or description for terms like "data sync", "file transfer", or speed ratings (e.g. 480Mbps/10Gbps). 2. Test by connecting your device to a computer: Android phones should show a file transfer notification, while iPhones will appear in iTunes/Finder. 3. Visually inspect USB-A connectors - data cables have four or more metal pins inside, while charge-only cables typically have only two pins. Note that USB-C and Lightning cables require functional testing as they lack visual indicators.