If it's built into Windows, you're probably looking for Windows Remote Assistance. KRDC is not built into Windows, it's actually built into KDE, a Linux desktop environment. KRDC would use RDP to connect to a Windows computer. Windows 7 Professional, Enterprise and Ultimate include a RDP server, and all versions of Windows 7 include a native RDP client called "Remote Desktop Connection" (
The difference is, remote desktop would give them complete control. In fact, you can't even see your screen because only one person can be logged into one account at any time. Someone connecting using remote desktop would log you out (and would need your username and password). Remote assistance allows you to see the screen, see what they are doing and retain control - they only have what permissions you grant.