Which programming languages aren't considered high-level?

Question

In informatics theory I hear and read about high-level and low-level languages all time.

Yet I don't understand why this is still relevant as there aren't any (relevant) low-level languages except assembler in use today.

So you get:

Low-level

• Assembler

Definitely not low-level

• C
• BASIC
• FORTRAN
• COBOL
• ...

High-level

• C++
• Ruby
• Python
• PHP
• ...

And if assembler is low-level, how could you put for example C into the same list. I mean: C is extremely high-level compared to assembler. Same even for COBOL, Fortran, etc.

• So why does everybody keep mentioning high and low-level languages if assembler is really the only low-level language?

Answer 1

Purely guessing here, but this may be a case of language-shift, whereby the distinction between low- and high-level langauges is slowly evolving in peoples' minds into the difference between managed- and unmanaged-languages, typed-and untyped-languages etc.etc. (at least in the way people are using the terminology).

Answer 2

You will find that

many of the truths we cling to depend upon our own point of view.

For a C programmer, Assembler is a low-level language. For a Java programmer, C is a low-level language and so on.

I suspect the folks programming the first stored-program computer with 1s and 0s would have thought Assembler a high-level language. It's all relative.

(Quote from Return of the Jedi)

Answer 3

According to Wikipedia, the low level languages are machine code and assembly.

From the source:

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 between the language and machine language; because of this, low-level languages are sometimes described as being "close to the hardware."

Then, to answer:

So why does everybody keep mentioning high and low-level languages if assembler is really the only low-level language.

I don't know who "everyone" is, but I would venture a guess that back when high-level languages were not as commonplace as they are today, it was more relevant to talk about low-level vs. high-level (because there was a relatively significant amount of programmers writing assembly code). In modern times it is a less important distinction. Personally, I rarely hear people using these terms except to differentiate between assembly or not (except for those times when you might hear someone raised on Python referring to C or C++ as low-level, but this is not in the spirit of the original definition).

Answer 4

You're asking a relatively subjective question; it's a question about terminology, that vernacular, and perspective.

For example, is Lisp a high-level or a low-level language? What if the implementation is running on a Lisp Machine?

Often, when people attempt to build a spectrum from low-level to high-level, what they are trying to quantify is a degree of "closeness to the hardware" as opposed to the degree of "abstraction."

Qualities which count toward an implementation's closeness to the hardware:

• The programmer directly controls the memory layout of data and has access at run-time to memory addresses of data.
• Mathematical operations are defined in terms of the hardware or loosely defined in order to conform to different types of hardware.
• There may be a library providing dynamic memory allocation, but use of dynamic memory is manual.
• Management of memory during string manipulation is manual.

Converse qualities which count toward an implementation's abstraction from the hardware:

• The programmer does not have run-time access to address of data (references instead of pointers).
• Mathematical operations are defined in specific terms not tied to specific hardware. (e.g., ActionScript 3 supports the Number type which self-converts from integer to floating-point rather than experience overflow.)
• Management of dynamic memory is handled by the environment, possibly through reference counting, garbage collection, or another automated memory management scheme.
• Management of memory during string manipulation is always hidden from the programmer and handled by the environment.

Other qualities might render a language very abstract compared to the hardware on which it runs:

• Declarative, search-based syntax. (e.g. Prolog)

With factors like these in mind, I would revise the spectrum you have written as follows:

Lowest level:

• Assembly language of the platform in question.

Low-level languages with higher-level flow control than assembly:

• C, C++
• Pascal

High-level languages:

• FORTRAN
• COBOL
• Python
• Perl

Highest-level languages:

• PROLOG
• Python
• Scheme

Python appears twice by intent -- it spans a portion of the spectrum depending on how the code is written.

Answer 5

As low-level, I would add:

• .NET IL
• Java JVM
• Other P-Code used in environments like VB6

Answer 6

To a large extent, "low-level" and "high-level" not binary categories but are a continuum. There are some languages that are clearly low-level (assembly, machine code), but beyond that there is really only "higher-level" and "lower-level".

As I see it, "lower-level" languages require code that looks more like the architecture of the computer, and "higher-level" languages accept code that looks more like the structure of the problem. But with that, languages can be high-level for one problem and low-level for another.