The IT Stuff

WLAN uses the radio waves at the Physical layers
WLAN use CSMA/CA(collision Avoidance) for Media Access
LAN use CSMA/CD(collision Detection) for Media Access
WLAN use Two way radio (half duplex ) for communication.
WLAN have the following problems

Coverage Probelms
Interference
Noise

To Share bandwidth Access point are used in WLAN instead of Ethernet Hub in LAN
WLANs must meet country specific RF regulation [...]

In the 802.11n draft, the first requirement is to support an OFDM implementation that improves upon the one employed in the 802.11a/g standards, using a higher maximum code rate and slightly wider bandwidth.
When  every possible option enabled, 802.11n could offer raw data rates up to 600 Mbps. In 2006, for example, most draft-n WLAN hardware [...]

Dual band (also known as dual-band or dualband) refers to functionality that allows a device  to support two frequency bands.
Dual-band technology allows you to operate in both the 2.4 and 5 GHz radio bands simultaneously, so it effectively doubles your available wireless bandwidth.
You could set up your network to handle time-sensitive gaming, music or video [...]

To start with the Wireless Networking , you must know the following things
1. Wireless LAN Card or Ethernet Adopter
Today most of the laptops have builtin Wireless LAN Card, If you have not , please buy a new one.  In short you need one wireless network adaptor for each computer or device that you wish to [...]

802.11
Developed as a standard by the Institute of Electrical and Electronic Engineers (IEEE, or I-triple-E), 802.11 is a radio technology used for wireless local area networks (WLANs). 802.11 is the parent standard of several technologies operating across several different frequencies.The 802.11 specification defines three types of wireless LAN, all operating at a data transmission rate [...]