Designed for concurrency
from the ground up,
the Erlang language can be
a valuable tool to help
solve concurrent problems.

Jim Larson, Google

Erlang is a language developed to let mere mortals write, test, deploy, and debug fault-tolerant concurrent software. ¹ Developed at the Swedish telecom company Ericsson in the late 1980s, it started as a platform for developing soft realtime software for managing phone switches. ² It has since been open-sourced and ported to several common platforms, finding a natural fit not only in distributed Internet server applications, but also in graphical user interfaces and ordinary batch applications.

Erlang’s minimal set of concurrency primitives, together with its rich and well-used libraries, give guidance to anyone trying to design a concurrent program. Erlang provides an effective platform for concurrent programming for the following reasons:

• The language, the standard libraries (Open Telecom Platform, or OTP), and the tools have been designed from the ground up for supporting concurrency.

• There are only a few concurrency primitives, so it’s easy to reason about the behavior of programs (though there are limits to how easy this can ever be).

• The implementation makes the simple primitives fast and scalable, and makes effective use of modern multicore hardware, eliminating the need for more complex mechanisms.

• The execution model eliminates some classes of errors from unsynchronized access to shared state—or at least makes these errors more noticeable.