You're probably already familiar with the SIM card, a tiny chip in your phone that connects it to your cell phone carrier of choice. For years, this chip was on a physical card that you could swap in ...

Use a SIM ejector tool or paperclip to gently remove the SIM tray. Take out the SIM card and inspect it for damage, such as ...

These two ways of connecting your phone to a cellular network are very different. We tell you about each and how you can switch from one to another. I started my career with CNET all the way back in ...