Chapter 9 discusses Remote Procedure Calls (RPCs). The
different directories each contain a different RPC server and
client application. In some versions the client will 
automatically connect to the server, while in others you
must specify the server name in the client code. See the
book for more information.

In some examples:
YOU MUST LOAD THE TCP/IP PACKAGE IN THE NETWORK APPLET OF THE
CONTROL PANEL BEFORE ANY TCP/IP CODE WILL WORK. SEE THE BOOK
"Windows NT Administration: From Single Systems to 
Heterogeneous Networks" FOR INSTRUCTIONS. Alternatively you
can modify the transport specification in the IDL files
to eliminate the use of the TCP/IP transport mechanism.

context - Demonstrates context handles
explicit - Demonstrates explicit handles
implicit - Demonstrates implicit handles
implict2 - demonstrates a second variation on implicit handles
mfc - Shows how to use RPCs in the mandelbrot code seen in Chapter 6
mfc2 - Improved version of mfc takes better advantage of RPC mechanism
simple - Simplest possible auto-binding example of an RPC server and client

See the book for directions on compiling and running the code.
In the case of the "simple" directory, you can type NMAKE
to make the client and server, and then run the client and
server on any two machines on the network. However, a number
of things can go wrong and the book will alert you to these
problems. 

All directories contain an additional readme file containing
compilation instructions.