The two major categories of wireless Internet access are cellular wide area networks (WANs) and Wi-Fi local area networks (LANs). In a nutshell, cellular is everywhere, although it may be poor or nonexistent inside a building or in rural locations. Wi-Fi reception is within a Wi-Fi hotspot, which varies from approximately 50 to a couple hundred feet from the transmitter (access point). Cellular - Long Range - Nationwide Cellular 3G/4G service is built into smartphones, which of course are cellphones, but cellular is also an option for tablets and laptops. To add cellular service to a Wi-Fi-only tablet, see cellular hotspot. To add cellular to a laptop, see cellular modem. Wi-Fi - Short Range - Local Wi-Fi is standard equipment on most mobile devices, and a Wi-Fi hotspot for Internet access is built into the wireless router commonly used at home or in a small office (see wireless router and Wi-Fi extender). When not at home, free Wi-Fi hotspots are available in public areas such as coffee shops and lounges, as well as on the street in many neighborhoods. However, airports and other venues may charge for access. See Wi-Fi hotspot and Muni Wi-Fi. Which Is Faster? Cellular data service may be slower, the same or faster than Wi-Fi. For example, 3G service in a crowded city may be slower or the same as a busy public Wi-Fi hotspot, but it will crawl compared to Wi-Fi at home with fast cable or FiOS access to the Internet. However, 4G cellular may be much faster than public Wi-Fi or even home Wi-Fi with a slow DSL connection to the Internet. See cellular generations and Wi-Fi vs. Ethernet.