A hacker could sit out in the parking lot and gather information from it through laptops and/or other devices, or even break in through this wireless card–equipped laptop and gain access to the wired network.
Issues can arise in a supposedly non-wireless organization when a wireless laptop is plugged into the corporate network.
Since most 21st-century laptop PCs have wireless networking built in (see Intel "Centrino" technology), they don't need a third-party adapter such as a PCMCIA Card or USB dongle.
Built-in wireless networking might be enabled by default, without the owner realizing it, thus broadcasting the laptop's accessibility to any computer nearby.
Modern operating systems such as Linux, mac OS, or Microsoft Windows make it fairly easy to set up a PC as a wireless LAN "base station" using Internet Connection Sharing, thus allowing all the PCs in the home to access the Internet through the "base" PC.
However, lack of knowledge among users about the security issues inherent in setting up such systems often may allow others nearby access to the connection.
Today there are a great number of security risks associated with the current wireless protocols and encryption methods, as carelessness and ignorance exists at the user and corporate IT level.