A network connects computers, peripherals, smart phones and other wireless devices, so they can communicate with each other remotely. The three most widely recognized types of networks (based on size) are:
Local-Area Networks (LANs) which connects computers and peripherals to a server, usually within a home or a commercial building. These are most commonly connected via wired Ethernet and WiFi (wireless LAN).
Metropolitan Area Networks (MANs) encompasses a distinct geographic area, most commonly connecting devices and computers within an entire city or region.
Wide-Area Networks (WANs) have no geographical limitations and can connect devices located anywhere on earth. A WAN consists of the fiber-optic cables, telephone cables, and communications satellites connecting every country on earth. Without WANs the largest network ever built (the Internet) simply could not exist.