Editing Abstract machine (section)

=== Imperative languages ===
In the late 1950s, the [[Association for Computing Machinery|Association for Computing Machinery (ACM)]] and other allied organisations developed many proposals for [[UNCOL|Universal Computer Oriented Language (UNCOL)]], such as [[Conway's Game of Life|Conway's machine]]. The UNCOL concept is good, but it has not been widely used due to the poor performance of the generated [[code]]. In many areas of computing, its performance will continue to be an issue despite the development of the [[Java virtual machine|Java Virtual Machine]] in the late 1990s. [[ALGOL|Algol Object Code]] (1964), P4-machine (1976), [[UCSD Pascal|UCSD P-machine]] (1977), and [[Forth (programming language)|Forth]] (1970) are some successful abstract machines of this kind.<ref name=":1" />