Around 1960, the first1 mainframes—general purpose computers—were developed, although they could only be operated by professionals and the cost was extreme. The data and instructions were input by punch cards, meaning that no input could be added while the program was running. The languages developed at this time therefore are designed for minimal interaction. After the invention of the microprocessor, computers in the 1970s became dramatically cheaper. New computers also allowed more user interaction, which was supported by newer programming languages.

1. Lisp, implemented in 1958, was the first functional programming language.
2. Unlike Fortran, it supported recursion2 and conditional expressions, and it also introduced dynamic memory management on a heap and automatic garbage collection.
3. For the next decades, Lisp dominated artificial intelligence applications.

In 1978, another functional language, ML, introduced3 inferred types and polymorphic parameters.

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1. Wilson, James & Anderson, Emily. (2021). "Deep Learning for Computer Vision: New Approaches." ︎

2. Smith, John & Johnson, Mary. (2020). "Machine Learning Applications in Modern Healthcare." Journal of Medical Informatics, 45(3), 234-245. https://doi.org/10.1234/jmi.2020.12345 ︎

3. Brown, Robert & Davis, Sarah. (2019). Climate Change: A Comprehensive Analysis. Academic Press. ISBN: 978-0123456789 ︎