"NIS, released by Sun in the 1980s, was the first 'prime time'
administrative database. It was originally called the Sun Yellow
Pages, but eventually had to be renamed for legal reasons. NIS
commands still begin with the letters yp, so it's hard to forget
the original name. NIS was widely adopted among Unix vendors and is
supported by every Linux distribution...
"The unit of sharing in NIS is the record, not the file. A
record usually corresponds to one line in a config file. A master
server maintains the authoritative copies of system files, which
are kept in their original locations and formats and are edited
with a text editor just as before. A server process makes the
contents of the files available over the network. A server and its
clients constitute an NIS 'domain...'"