levels of programming languages

High-level programming language

 

 

 

A high-level programming language is a programming language that, in comparison to low-level programming languages, may be more abstract, easier to use, or more portable across platforms. Such languages often abstract away CPU operations such as memory access models and management of scope.

Features of high-level languages

The term "high-level language" does not imply that the language is always superior to low-level programming languages but rather refers to the higher level of abstraction from machine language. Rather than dealing with registers, memory addresses and call stacks, high-level languages deal with variables, arrays and complex arithmetic or boolean expressions. In addition, they have no opcodes that can directly compile the language into machine code, unlike low-level languages like Assembly language. Other features such as string handling routines, object-oriented language features and file input/output may also be present.

In general, high-level languages make complex programming simpler, while low-level languages tend to produce more efficient code. In a high-level language, complex elements can be broken up into simpler, though still fairly complex, elements for which the language provides abstractions, keeping programmers from having to "reinvent the wheel." The cost of this convenience is often less efficient code overall. For this reason, code which needs to run particularly quickly and efficiently may be written in a lower-level language, even if a higher-level language would make the coding easier.

 

Note that the terms "high-level" and "low-level" are inherently relative. Originally, assembly language was considered low-level and COBOL, C, etc. were considered high-level, as they allowed the abstractions of functions, variables and expression evaluation, and also that they had to be compiled to assembly before being compiled into machine code. Many programmers today might refer to C as low-level, as it still allows memory to be accessed by address, and provides direct access to the assembly level. 

Low-level programming language

 

In computer science, a low-level programming language is a language that provides little or no abstraction from a computer's microprocessor. The word "low" does not imply that the language is inferior to high-level programming languages but rather refers to the small or nonexistent amount of abstraction between the language and machine language; because of this, low-level languages are sometimes described as being "close to the hardware."

"High-level" and "low-level" are also used relatively; a Java programmer might consider C to be a comparatively low-level language.

Low-level programming languages are sometimes divided into two categories: first generation, and second generation.