Spyware is a type of malware that secretly monitors users' online activities to gain access to personal information like banking details without consent. It can be bundled with other downloads or installed through email attachments. Symptoms of spyware may include new icons appearing in the taskbar, redirects during web searches, and random error messages. Users should use antivirus software with anti-spyware tools to detect, remove, and prevent spyware infections, as well as practice safe browsing and downloading habits. Regularly updating software and higher browser security can also help avoid spyware.