What is a programming language?

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Programming basics[1]

A programming language is a formal computer language or constructed language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs to control the behavior of a machine or to express algorithms.[2]

Essential features of a programming language[edit]

Do I understand essential features?[edit]

If you are still stuck, or you have other questions, you may want to ask a question on our discussion board.

Fixed vocabulary[edit]

Instructions for operations do not change. For example, the command print will always print. We do not use instructions like "display" or "show" or "put on screen", we always use the same vocabulary. Each programming language has it's own vocabulary, but this vocabulary must be consistent throughout the language.

Unambiguous meaning[edit]

Instructions must be clear. Instructions should not be foggy or fuzzy (ambiguous). For example, if I want to return the absolute value of a number, I would use the instructions below:

# the built-in function for absolute value is abs(). 

abs(-212)

Consistent grammar & syntax[edit]

Throughout the programming language, the way we declare and use language features must be the same. Again, instructions must be very clear. For example, a conditional statement must always be formatted the same way. In python the use of whitespace is always the same.

if x > 0:
    print('X is greater than zero')
else:
    print(' X is equal or greater than zero')


The basics of programming languages[edit]

In order to really understand this material, we must understand the ALU - the "brain" of the computer.

An example[edit]

Below is an example of a program language designed to communicate instructions to a machine. The piano is "fed" instructions which enable it to play a simple song. The song is an example of a program. Can you imagine how difficult it might be to "write" these instructions?!?

Explain the need for higher level languages.[edit]

If you have watched the example above, you might immediately realize it would be crazy to write a complex piano piece by punching holes in a piece of paper. This is why we use high-level languages.

We need high level languages because programs are highly complex. Even a simple conditional statement would take many hours to write in assembly. Debugging our code would be almost impossible and understanding the code would be almost impossible. ]

Standards[edit]

  • State the fundamental operations of a computer.
  • Distinguish between fundamental and compound operations of a computer.
  • Explain the essential features of a computer language.
  • Explain the need for higher level languages.
  • Outline the need for a translation process from a higher level language to machine executable code.

References[edit]

A unit of abstract mathematical system subject to the laws of arithmetic.

Give a detailed account including reasons or causes.

Give a specific name, value or other brief answer without explanation or calculation.

Give a specific name, value or other brief answer without explanation or calculation.

Make clear the differences between two or more concepts or items.

Give a brief account.