Editing Erlang (programming language) (section)

===Processes===
Erlang applications are built of very lightweight Erlang processes in the Erlang runtime system. Erlang processes can be seen as "living" objects ([[object-oriented programming]]), with data encapsulation and [[message passing]], but capable of changing behavior during runtime. The Erlang runtime system provides strict [[process isolation]] between Erlang processes (this includes data and garbage collection, separated individually by each Erlang process) and transparent communication between processes (see [[Location transparency]]) on different Erlang nodes (on different hosts).

Joe Armstrong, co-inventor of Erlang, summarized the principles of processes in his [[Doctor of Philosophy|PhD]] [[thesis]]:<ref>{{Cite thesis |last=Armstrong |first=Joe |title=Making reliable distributed systems in the presence of software errors |date=20 November 2003 |degree=DTech |publisher=The Royal Institute of Technology |place=Stockholm, Sweden}}</ref>

*Everything is a process.
*Processes are strongly isolated.
*Process creation and destruction is a lightweight operation.
*Message passing is the only way for processes to interact.
*Processes have unique names.
*If you know the name of a process you can send it a message.
*Processes share no resources.
*Error handling is non-local.
*Processes do what they are supposed to do or fail.

Joe Armstrong remarked in an interview with Rackspace in 2013: "If [[Java (programming language)|Java]] is '[[write once, run anywhere]]', then Erlang is 'write once, run forever'."<ref>{{cite AV media |last=McGreggor |first=Duncan |date=26 March 2013 |title=Rackspace takes a look at the Erlang programming language for distributed computing |medium=Video |language=en |url=https://www.youtube.com/watch?v=u41GEwIq2mE&t=3m59s | archive-url=https://ghostarchive.org/varchive/youtube/20211211/u41GEwIq2mE| archive-date=2021-12-11 | url-status=live|publisher=Rackspace Studios, SFO |access-date=24 April 2019}}{{cbignore}}</ref>