Performance Center Virtual users is a general term that can reference any type of Vuser that uses any of the supported protocols (Web HTTP/ HTML, Java Replay, Remote Desktop, Winsock, etc).

Remote Desktop Virtual Users refers to a specific protocol.

Micro Focus states the following in regards to the RDP protocol:

''The Microsoft RDP (Remote Desktop Protocol) enables one computer [the client] to connect to another computer [the server] over a network connection. For example, you can use RDP to connect to a central, powerful server for working on specific business applications or graphic terminals. This provides you with the same look and feel as if you are working on a standalone PC. The client computer employs RDP client software for this purpose, while the other computer must run RDP server software. The client software is referred to as Remote Desktop Connection. The server software is referred to as Remote Desktop Services.''

Note that when other protocols will not work, typically you can use RDP.

Hope this helps.