Computer Network Services: Domain Name Servers (DNS)
The translation from a computer name to an IP address (e.g. obelisk.bu.edu => 128.197.10.22) is done through a (potentially long) sequence of interactions between the client and a number of “Domain Name Servers” (DNS).
This process is analogous to calling the “Bell Atlantic” directory (i.e. 411) to figure out the phone number of a person that you know only by name and by the city/town in which he/she lives.