AT&T is a telecommunications company offering a range of services including wireless plans, internet, accessories, and prepaid options. They provide deals on phones and devices, with a focus on high-speed internet through AT&T Fiber. Additionally, AT&T offers promotions such as getting the latest Samsung and iPhone models with eligible trade-ins. The company also emphasizes connectivity with initiatives like the Mother's Day gift guide and unlimited data plans. AT&T caters to both personal and business customers, aiming to provide reliable network services and innovative solutions.