From A. K. Erlang
erlang - Computer Definition
A measure of the traffic intensity of a transmission facility, such as a circuit or channel. One Erlang is the maximum traffic that a facility can support during an hour, and is equivalent to 36 CCS. The Erlang measurement is named for A.K. Erlang, the Danish mathematician and traffic engineer who developed the various Erlang traffic engineering models. See also Erlang, H. K.; Erlang B; Extended Erlang B; Erlang C; Equivalent Queue Extended Erlang B; GoS; Poisson distribution; traffic; and traffic engineering.
(1) A unit of measurement of telephone traffic. It is equal to one hour of conversation (3,600 seconds or 36 CCS). Named after the Danish mathematician Agner Krarup Erlang, it also specifies the approximate number of trunks in use; for example, if the traffic in a call center is 8.5 Erlangs in one hour, more than 8 trunks were used in that hour. See CCS.
(2) An open source programming language specialized for concurrent processing (multiprocessing) on Unix-based and Windows computers. Originally developed by Ericsson and named after A. K. Erlang (see definition #1 above) as well as "Ericsson Language," Erlang makes programming threads easier to write than in traditional languages. Developed in the late 1980s, Erlang was modeled after concurrent languages such as Ada and Modula and functional languages such as ML and Miranda. For more information, visit www.erlang.org and www.erlang.se. See thread and multithreading.