Wireless networks have two modes of operation infrastructure and adhoc. Adhoc mode is used to allow a number of computers without a dedicated wireless device to network and share data. This is problematic as your wireless laptop can end up being casually connected to any number of other computers or an attacker may use it to get ranged access to the laptop without your approval. Wireless systems advertising themselves posing as legitimate hotspots that then take your credit card details and sniff all of your traffic or poison replies to include malicious code.”]
Source: https://nakedsecurity.sophos.com/2009/08/05/guest-blog-viral-ssids-wiphishing-wireless-reputation/