Wireless networks works without the use of physical cable.  It use a wireless (radio)  protocol that enable each device on the network to communicate the same way as a wired network.  A wireless switch or Wireless Access Point (WAP) will act as the central communication point for all devices on the network.

A server based wireless network have a server computer on the network that is used to control access to files and printing resources.

The advantage to this type of network is the ability to manage access to resources on the network.  Wireless networks are less costly than wired networks.  No cables have to be run to each device.

The disadvantage is that computers have to stay within close promixity (150 feet) of the Wireless Access Point.  However, this disadvantage can be overcome with a signal amplifier.