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'{{Unreferenced|date=December 2009}} In [[computer science]], a '''low-level programming language''' is a [[programming language]] that provides little or no abstraction from a computer's [[instruction set architecture]]. The word "low" refers to the small or nonexistent amount of [[abstraction (computer science)|abstraction]] between the language and [[machine language]]; because of this, low-level languages are sometimes described as being "close to the hardware." Low-level languages can be converted to machine code without using a compiler or interpreter, and the resulting code runs directly on the processor. A program written in a low-level language can be made to run very fast, and with a very small memory footprint; an equivalent program in a high-level language will be more heavyweight. Low-level languages are simple, but are considered difficult to use, due to the numerous technical details which must be remembered. By comparison, a [[high-level programming language]] isolates the execution semantics of a computer architecture from the specification of the program, which simplifies development. Low-level programming languages are sometimes divided into two categories: ''first generation'', and ''second generation''. Ha. Ha. Ha. ==First generation== The first-generation programming language, or ''1GL'', is [[machine code]]. It is the only language a microprocessor can process directly without a previous transformation. Currently, programmers almost never write programs directly in machine code, because it requires attention to numerous details which a high-level language would handle automatically, and also requires memorizing or looking up numerical codes for every instruction that is used. For this reason, second generation programming languages provide one abstraction level on top of the machine code. Example: A function in 32-bit [[x86]] machine code to calculate the ''n''th [[Fibonacci number]]: <pre> 8B542408 83FA0077 06B80000 0000C383 FA027706 B8010000 00C353BB 01000000 B9010000 008D0419 83FA0376 078BD98B C84AEBF1 5BC3 </pre> ==Second generation== The second-generation programming language, or ''2GL'', is [[assembly language]]. It is considered a second-generation language because while it is not a microprocessor's native language, an assembly language programmer must still understand the microprocessor's unique architecture (such as its ''registers'' and ''instructions''). These simple instructions are then assembled directly into machine code. The assembly code can also be abstracted to another layer in a similar manner as machine code is abstracted into assembly code. Example: The same [[Fibonacci number]] calculator as above, but in x86 assembly language using [[MASM]] syntax: <pre> fib: mov edx, [esp+8] cmp edx, 0 ja @f mov eax, 0 ret @@: cmp edx, 2 ja @f mov eax, 1 ret @@: push ebx mov ebx, 1 mov ecx, 1 @@: lea eax, [ebx+ecx] cmp edx, 3 jbe @f mov ebx, ecx mov ecx, eax dec edx jmp @b @@: pop ebx ret </pre> ==See also== * [[High-level programming language]]s * [[Very high-level programming language]]s * [[Categorical list of programming languages]] {{Programming language}} {{Template:X86_assembly_topics}} {{DEFAULTSORT:Low-Level Programming Language}} [[Category:Programming language classification]] {{Compu-lang-stub}} [[ca:Llenguatge de baix nivell]] [[el:Γλώσσα προγραμματισμού χαμηλού επιπέδου]] [[es:Lenguaje de bajo nivel]] [[fa:زبان برنامه‌نویسی سطح پایین]] [[fr:Langage de bas niveau]] [[ko:저급 프로그래밍 언어]] [[hr:Programski jezik niske razine]] [[it:Linguaggio di programmazione a basso livello]] [[lv:Zema līmeņa programmēšanas valoda]] [[hu:Alacsony szintű programozási nyelv]] [[mk:Прости програмски јазици]] [[mn:Доод түвшний програмчлалын хэл]] [[ja:低水準言語]] [[pl:Język niskiego poziomu]] [[pt:Linguagem de programação de baixo nível]] [[ru:Низкоуровневый язык программирования]] [[sl:Nizkonivojski jezik]] [[sh:Programski jezik niske razine]] [[sv:Lågnivåspråk]] [[th:ภาษาระดับต่ำ]] [[tr:Düşük seviye programlama dili]] [[vi:Ngôn ngữ lập trình bậc thấp]] [[zh:低级语言]]'