A wireless Access Point (AP) connects a group of wireless stations to an adjacent wired (Typically, Ethernet) LAN. An AP is like an Ethernet hub - except that a hub relays LAN frames only to other 802.3 stations, whereas an AP relays 802.11 frames to all other 802.11 or 802.3 stations in the same subnet. (In English: "it allows communication between wired and wireless..") A wireless router connects a group of wireless stations to an adjacent wired (Typically, Ethernet) LAN. A wireless router is a wireless AP combined with an Ethernet router. A wireless router forwards IP packets between your wireless subnet and any other subnet. Most routers also have a built-in firewall, and built-in Ethernet ports. (In English: same as an AP, but you can network different subnets or networks (Example: your home network and the[Modem also required typically!] )
The function of a wireless access point is to allow wireless devices such as projectors, laptops and PDAs to access a local area network. Wireless access points mainly act as switches to spread connections wirelessly. The difference between an access point and a router is that access points do not assign IP addresses nor do they have firewalls; they only lock out traffic that does not have the wireless key.
A wireless router bridge is a way to use an old or unneeded wireless router to extend the usable range of a central Internet access point. This can be done by connecting an older router to a functioning router and then either changing the wireless mode of the router to bridge, or by changing the firmware inside of the router so it can support bridging. The end result is a wireless router that will pick up the signal from an access point and provide Internet access to any computer that uses the wireless router bridge.
"A wired router has to be plugged into your computer, or whatever you are wanting connect to the internet via an ethernet cable. A wireless router sends the internet signal to your device. It is similar to the way a wireless phone works. The wireless router can also be used as a wired router. The wired router is more secure and faster than the wireless router, but the wireless is easier to set up. You can also use multiple devices on a wireless router."