Hubs, Switches, Routers, and Access Points are all used to connect computers together on a network, but each of them has different capabilities.
Hubs are used to connect computers on a network so as to communicate with each other. Each computer plugs into the hub with a cable, and information sent from one computer to another passes through the hub.
Switches functions the same way as hubs, but they can identify the intended destination of the information that they receive, so they send that information to only the computers that its intended for.
Access points provide wireless access to a wired Ethernet network. An access point plugs into a hub, switch, or wired router and sends out wireless signals. This enables computers and devices to connect to a wired network wirelessly. You can move from one location to another and continue to have wireless access to a network. When you connect to the Internet wirelessly using a public wireless network in an airport, hotel or in public, you are usually connecting through an access point. Some routers are equipped with a wireless access point capability, in this case you don’t need a wireless access Point.