This type of network is gaining popularity because it is fairly cheap and easy to handle and allows you to go online wherever you choose to place your PC in your home.
Wireless networks tend to use a standard set of protocols and often operate with a signal range in excess of the boundaries of your home. It is therefore possible that someone with the correct equipment could monitor the traffic on your network, use your Internet connection and access files on any PCs that are connected to the network.
It is always a good idea to assign a security key to your wireless network so that any PC wanting to connect would have to enter this pre-determined key.
Follow the recommendations
The most common practice is to connect a router directly to the Internet connection and, when you use wireless adapters on any PCs, to connect the adapters to the router. In this case, the wireless section of the network may be considered part of the Internet. You should follow the recommendations about protection of PCs against attacks both from the Internet and from the wireless network section in your home.
Encrypt internal networks
If you use a wireless network connecting several active PCs in your home in order to share resources on the internal network (for instance Internet connection, network printer, shared hard drive sections, etc.), you should always use an encrypted network and protect your PC.