Editing BESM (section)

==Models==
The BESM series included six models.

===BESM-1===
''BESM-1'', originally referred to as simply the BESM or BESM AN ("BESM Akademii Nauk", BESM of the Academy of Sciences), was completed in 1952.<ref>{{cite book|last1=Metropolis|first1=Nicholas|title=History of Computing in the Twentieth Century|date=2014|publisher=Elsevier|isbn=978-1-4832-9668-5|page=149|url=https://books.google.com/books?id=AsvSBQAAQBAJ&q=%22BESM%22+1952&pg=PA149|language=en}}</ref><ref>{{cite book|last1=Impagliazzo|first1=John|last2=Proydakov|first2=Eduard|title=Perspectives on Soviet and Russian Computing: First IFIP WG 9.7 Conference, SoRuCom 2006, Petrozavodsk, Russia, July 3-7, 2006, Revised Selected Papers|date=2011|publisher=Springer|isbn=978-3-642-22816-2|page=14|url=https://books.google.com/books?id=-jSqCAAAQBAJ&q=BESM+1952&pg=PA14|language=en}}</ref> Only one BESM-1 machine was built. The machine used approximately 5,000 [[vacuum tube]]s. At the time of completion, it was the fastest computer in Europe. The [[floating-point number]]s were represented as 39-bit [[Word (computer architecture)|word]]s: 32 bits for the [[Significand|mantissa]], one bit for sign, and 1 + 5 bits for the exponent. It was capable of representing numbers in the range 10<sup>&minus;9</sup> – 10<sup>10</sup>. BESM-1 had 1024 words of [[read–write memory]] using [[core memory|ferrite core]]s, and 1024 words of [[read-only memory]] based on semiconducting diodes. It also had external storage: four [[magnetic tape]] units of 30,000 words each, and fast [[Drum memory|magnetic drum]] storage with a capacity of 5120 words and an access rate of 800 words/second. The computer was capable of performing 8–10 [[SI prefix|K]] [[Flops]]. The energy consumption was approximately 30 [[kW]], not accounting for the cooling systems.

===BESM-2===
''BESM-2'' also used [[vacuum tube]]s.

===BESM-3M and BESM-4===
''BESM-3M'' and ''BESM-4'' were built using [[transistors]]. Their architecture was similar to that of the [[M-20 (computer)|M-20]] and [[M-220]] series.{{cn|date=April 2024}} The word size was 45 bits.{{cn|date=April 2024}} Thirty BESM-4 machines were built. BESM-4 was used to create the first ever [[computer animation]].<ref>{{cite web|url=http://www.etudes.ru/ru/mov/kittie/|script-title=ru:Кошечка - Математические этюды|language=ru|trans-title=Cat - Mathematical Etudes |archive-url=https://web.archive.org/web/20110510203746/http://www.etudes.ru/ru/mov/kittie/|archive-date=10 May 2011|url-status=live|access-date=28 May 2011}}</ref><ref>{{Cite web|url=http://www.geekosystem.com/kitty-computer-animation-russia-1968-video/|title="Kitty": One of the First-Ever Computer Animations|website=www.geekosystem.com|date=22 March 2010 |language=en|access-date=21 April 2018}}</ref> The prototypes of both models were made in 1962–63, and the beginning of the series release was in 1964.<ref>{{Cite book|url=https://books.google.com/books?id=fLCEXWkQXvQC&q=%D0%B1%D1%8D%D1%81%D0%BC-3%D0%BC&pg=PA401|title=Профессиональное программирование. Системный подход, 2 изд.|last=Олегович|first=Одинцов Игорь|date=2004|publisher=БХВ-Петербург|isbn=5-94157-457-6|page=401|language=ru|trans-title=Professional programming. A Systems Approach, 2nd ed.}}</ref>

[[Epsilon macro language|EPSILON]] (a [[Macro (computer science)|macro language]] with high-level features including strings and lists, developed by [[Andrey Ershov]] at [[Novosibirsk]] in 1967) was used to implement [[ALGOL 68]] on the M-220.<ref>{{cite web|title=EPSILON macro language| url=http://foldoc.org/index.cgi?query=EPSILON&action=Search|access-date=29 May 2007}}</ref>

===BESM-6===
[[File:BESM-6 (London Science Museum).jpg|thumb|[[BESM-6]] at [[London Science Museum]]]]
{{Main|BESM-6}}
The [[BESM-6]] was the best-known and most influential model of the series. The design was completed in 1965. Production started in 1968 and continued for the following 19 years.<ref>[http://old.osp.ru/museum/story/01_00.htm Очерки по истории советской вычислительной техники и школ программирования  (Издательство "Открытые Системы")] [Essays on the history of Soviet computer technology and programming schools (Open Systems Publishing)], (in Russian), {{webarchive|url=https://web.archive.org/web/20070930154907/http://old.osp.ru/museum/story/01_00.htm|date=30 September 2007}} [https://translate.google.com/translate?sl=auto&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=https%3A%2F%2Fweb.archive.org%2Fweb%2F20070930154907%2Fhttp%3A%2F%2Fold.osp.ru%2Fmuseum%2Fstory%2F01_00.htm&edit-text= Google translation].</ref>