There are five indexes you can retrieve:
 
Command                 Description
=================================================================
INDEX                   This master list of other indexes
FYI INDEX               Index to For Your Information series (FYIs)
IEN INDEX               Index to Internet Experimental Notes (IENs)
RFC INDEX               Index to Request For Comments series (RFCs)
NETINFO INDEX           Index to Network Information Center documents
 
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into the first nonblank line of your message), or send "HELP" for
instructions on using SERVICE.
Send questions, comments to NIC@NIC.DDN.MIL.