A guide to SIM cards, the small chips that connect your phone to a cellular network

SIM cards are tiny chips stored inside many cell phones.
Tongchai Cherdchew / EyeEm/Getty Images
A SIM card, or subscriber identity module, is a small card in your cellphone that connects you to the network.
Your SIM card contains your phone number, and lets you make phone calls, send text messages, and more.
SIM cards have evolved over the years and come in several sizes, including mini-, micro-, and nano-SIMs.Visit Insider's Tech Reference library for more stories.
Most mobile phones rely on