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{{Short description|Programming language with strong abstraction from details of hardware}}
{{Use American English|date=January 2019}}
▲{{Use American English|date=January 2019}}In [[computer science]], a '''high-level programming language''' is a [[programming language]] with strong [[Abstraction (computer science)|abstraction]] from the details of the [[computer]]. In contrast to [[low-level programming language]]s, it may use [[natural language]] ''elements'', be easier to use, or may automate (or even hide entirely) significant areas of computing systems (e.g. [[memory management]]), making the process of developing a program simpler and more understandable than when using a lower-level language. The amount of abstraction provided defines how "high-level" a programming language is.<ref>[https://web.archive.org/web/20070826224349/http://www.ittc.ku.edu/hybridthreads/glossary/index.php HThreads - RD Glossary<!-- Bot generated title -->]</ref>
In the 1960s, a high-level programming language using a [[compiler]] was commonly called an ''[[autocode]]''.<ref name=kleith>{{cite book|last=London|first=Keith|year=1968|title=Introduction to Computers|publisher=Faber and Faber Limited|___location=24 Russell Square London WC1|isbn=0571085938|page=184|chapter=4, Programming|quote=The 'high' level programming languages are often called autocodes and the processor program, a compiler.}}<!--The book has no ISBN number, instead it has an SBN number. There is no typo in the prior sentence.--></ref>
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Examples of high-level programming languages in active use today include [[Python (programming language)|Python]], [[Visual Basic]], [[Delphi (programming language)|Delphi]], [[Perl]], [[PHP]], [[ECMAScript]], [[Ruby (programming language)|Ruby]], [[C Sharp (programming language)|C#]], [[Java (programming language)|Java]] and many others.
The terms ''high-level'' and ''low-level'' are inherently relative. Some decades ago, the [[C (programming language)|C language]], and similar languages, were most often considered "high-level", as it supported concepts such as expression evaluation, [[parameter]]ised recursive functions, and data types and structures, while [[assembly language]] was considered "low-level". Today, many programmers might refer to C as low-level, as it lacks a large [[Run time system|runtime]]-system (no garbage collection, etc.), basically supports only scalar operations, and provides direct memory addressing. It, therefore, readily blends with assembly language and the machine level of [[CPU]]s and [[microcontroller]]s. Also, in the introduction chapter of [[The C Programming Language]] (second edition) by K&R, C is considered as a relatively "low level" language.<ref>{{cite book|last1=Kernighan|first1=Brian W.|last2=Ritchie|first2=Dennis M.|date=1988|title=The C Programming Language: 2nd Edition|url=https://books.google.com.tw/books/about/The_C_Programming_Language/FGkPBQAAQBAJ|url-status=live|publisher=Prentice Hall|isbn=9780131103627|archive-url=https://archive.org/details/the_c_programming_language_2_20181213|archive-date=2018-12-13}}</ref>
Assembly language may itself be regarded as a higher level (but often still one-to-one if used without [[Macro (computer science)|macro]]s) representation of [[machine code]], as it supports concepts such as constants and (limited) expressions, sometimes even variables, procedures, and [[data structure]]s. [[Machine code]], in its turn, is inherently at a slightly higher level than the [[microcode]] or [[micro-operation]]s used internally in many processors.<ref>{{Cite book|title=The art of assembly language|last=Hyde, Randall.|date=2010|publisher=No Starch Press|isbn=9781593273019|edition= 2nd|___location=San Francisco|oclc=635507601|url=https://www.google.ca/books/edition/The_Art_of_Assembly_Language_2nd_Edition/sYHtTvQ-ObIC}}</ref>
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Note that languages are not strictly ''interpreted'' languages or ''compiled'' languages. Rather, implementations of language behavior use interpreting or compiling. For example, [[ALGOL 60]] and [[Fortran]] have both been interpreted (even though they were more typically compiled). Similarly, Java shows the difficulty of trying to apply these labels to languages, rather than to implementations; Java is compiled to bytecode which is then executed by either interpreting (in a [[Java virtual machine]] (JVM)) or compiling (typically with a just-in-time compiler such as [[HotSpot (virtual machine)|HotSpot]], again in a JVM). Moreover, compiling, transcompiling, and interpreting is not strictly limited to only a description of the compiler artifact (binary executable or IL assembly).
=== High-level language computer architecture ===
Alternatively, it is possible for a high-level language to be directly implemented by a computer – the computer directly executes the HLL code. This is known as a ''[[high-level language computer architecture]]'' – the [[computer architecture]] itself is designed to be targeted by a specific high-level language. The [[Burroughs large systems]] were target machines for [[ALGOL 60]], for example.<ref>{{Citation|last=Chu|first=Yaohan|chapter=Concepts of High-Level Language Computer Architecture|date=1975|pages=1–14|publisher=Elsevier|isbn=9780121741501|doi=10.1016/b978-0-12-174150-1.50007-0|title=High-Level Language Computer Architecture}}</ref>
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