Citrix is like Terminal Services. It's like, remotely connecting to virtual desktops
It is a bit more than that.
Citrix runs on Windows 2000 and allows for the delivery of applications to users in a way that Terminal Server acannot do: seamless.
That means when the user launches the application, they dont get a terminal server desktop and then laucnht he app, it actually pops up as the application on their desktop. you can run these apps over any connection, as the packets to and from the end user are SMALL. making it great for sites that don;t have allot of bandwith.
It is quite a product to be honest, and until Microsof can get their heads out of their a**, it will be around for awhile.
Seamless applications was supposed to be availabel in the whole .NET platform but it isn's.
Citrix also allows for the use of a universal driver for printers, allowing you to connect near any printer through your session to the application with minimal work.
You can do COM port and LTP mapping to the client workstation through the app.
Anywho! There you have it.
I currently run the following citrix environment:
1 citrix master server
1 citrix backup server
2 online web servers for user to logon to and get their apps on the web.
4 Windows NT Temrinal server edition systems
20 Citrix metaframe boxes.
Serving 11,000 users across the world...