What is a computer programming language?

Answer 1

Computer programming languages allow software developers to convert algorithms into machine code. In order for a machine to make sense of an algorithm it has to be encoded in a language the machine actually understands. Unfortunately, the only language the machine understands is its own native machine code and, worse, every machine type has its own specific variant of machine code.

Writing machine code is extremely difficult for a human, thus we use an intermediate language known as a programming language. Programming languages come in many forms, however they all provide a means of writing machine code in a more abstract form that is easier for humans to understand, yet simple enough for a computer to translate into machine code. Each language has its own set of rules that govern how expressions may be combined to form statements. Some languages are more expressive than others but, generally, the more high-level it is, the easier it becomes to translate an algorithm into code.

In order to instruct the computer we must first program it, but that would seem to create a paradox: we can't write a program if a computer can't translate the code we write, so how did we program the early computers? The answer is that the early pioneers wrote very primitive translators known as assemblers entirely in machine code. An assembler simply translates a human-readable, low-level symbolic code known as assembly language into machine code. Once you have an assembler you can use it to write a more complex translator known as a compiler, one that is capable of processing a higher level language. Over time, hundreds of different languages and their corresponding compilers have evolved, to the extent that if you now want to create a new programming language you simply use an existing language to write the translator.