NetInfo stored network-wide configuration information, such as users and groups, in a binary database consisting of directories that could optionally be obtained from a domain server.
NetInfo was introduced in NeXTSTEP version 0.9, and replaced both the Unix system configuration files and Sun Microsystems' Network Information Service (Yellow Pages) on NeXT computers.
[1] This meant basic tasks such as translating a UNIX UID to a user name string could stall because NetInfo was stuck on a DNS lookup.
Beginning with Mac OS X Leopard (10.5), NetInfo was completely phased out and replaced by a new local search node named dslocal, which uses standard property list files in /var/db/dslocal/.
It could also be viewed and modified through its application programming interface, the NetInfo Manager utility, or command line tools such as niutil.