AP here is the short name for an access point — the device, or the job inside a device, that lets phones and laptops join a wireless network. In a school or office, an AP may sit on the ceiling and cover one room; at home, the WiFi part of a router is doing the same work. People who set up networks say AP as if it were an ordinary noun: one AP, two APs, a weak AP. You say it as two letters, A-P. Though actually, the same two letters do many other jobs in English — a news agency, a US school exam — so this meaning lives in tech talk, not in a newspaper headline. A hotspot is close, but not the same thing: a hotspot is often a phone or a café sharing internet; an AP is the access point itself.