Grayware refers to unwanted programs like adware, spyware, and dialers that negatively impact computer performance. Adware displays ads, spyware collects user information, and malware is intended to harm computers. Grayware can be unintentionally installed through bundling or by downloading enhanced programs from untrusted sites. The existence of grayware on a network can reduce performance, increase crashes, lower efficiency, degrade bandwidth, and increase security risks. Users should keep software updated, browse carefully, only download from trusted sites, and use protection like firewalls and antivirus to detect and prevent grayware.