ShellHost, formally known as Shell Infrastructure Host (sihost.exe), is a critical Windows system process responsible for managing essential graphical elements of the Windows interface. It handles the Start Menu, taskbar transparency, desktop background, and other visual effects, ensuring smooth user experience. As a core component, it launches automatically with Windows and runs in the background. While ShellHost is legitimate, cyber attackers may disguise malware using similar names, making it important to verify the process location (usually in C:\Windows\System32). Disabling or tampering with ShellHost can cause system instability or loss of key interface features. Monitoring this process helps detect potential security risks.