The Advantages of Ad Hoc Networksby James T Wood
Ad hoc networks are wireless connections between two or more computers and/or wireless devices (such as a Wi-Fi enabled smart phone or tablet computer). A typical wireless network is based on a wireless router or access point that connects to the wired network and/or Internet. An ad hoc network bypasses the need for a router by connecting the computers directly to each other using their wireless network adapters.
Connecting to files on other computers and/or the Internet without the need for a wireless router is the main advantage of using an ad hoc network. Because of this, running an ad hoc network can be more affordable than a traditional network---you don't have the added cost of a router. However, if you only have one computer an ad hoc network won't be possible.
Ad hoc networks can be created on the fly in nearly any situation where there are multiple wireless devices. For example: emergency situations in remote locations make a traditional network nearly impossible, but "The medical team can utilize 802.11 radio NICs in their laptops and PDAs and enable broadband wireless data communications as soon as they arrive on the scene."
Creating an ad hoc network from scratch requires a few settings changes and no additional hardware or software. If you need to connect multiple computers quickly and easily, then an ad hoc network is an ideal solution.