QUESTION 01 · Program development

Define a programming language and name two language levels.

2 marks

Answer

A programming language provides symbols and rules for expressing instructions to a computer.

Machine language represents instructions the processor can execute.
High-level languages, such as C, express operations using readable statements.

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QUESTION 02 · Program development

What is a programming language? Compare machine, assembly and high-level languages.

5 marks

Answer in brief

A programming language is a set of words, symbols and rules used to write instructions for a computer.

Types of programming languages

Machine language: Instructions are written as machine codes, usually shown using 0s and 1s. The processor can execute the correct machine code directly. It is difficult for people to read and write.
Assembly language: Short names such as ADD are used instead of binary instructions. An assembler converts assembly code into machine code. The instructions depend on the processor.
High-level language: Instructions are written using readable words and expressions. Examples include C and Python. A suitable translator is needed before or during execution.

Example

To add two numbers in C, we can write total = a + b;. The compiler translates the C instructions for the selected computer. We do not need to write the processor’s binary instructions ourselves. The translated code may contain several machine instructions.

Advantages of high-level languages

Easy to read: Meaningful names and familiar expressions make programs easier to understand.
Easy to maintain: A programmer can find and change the required part more easily.
Better portability: The same source can often be used on different computers when suitable compilers and libraries are available.

Compiler and interpreter

A compiler translates a program into another form before the translated program runs. An interpreter carries out instructions through another program. These are ways of implementing a language. C programs are commonly compiled. A language and a compiler are different: C is a language, while GCC is one compiler that supports it.

Reference tables

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Levels of programming languages
Level	How instructions are written	Translation and use
Machine language	Encoded processor instructions, commonly represented as binary or hexadecimal	Executed by the matching processor; difficult for people to maintain.
Assembly language	Mnemonic instructions such as ADD, with symbolic labels	An assembler produces machine code for a particular architecture.
High-level language	Expressions, functions and control structures close to human reasoning	A compiler or interpreter implements the language. C source is commonly compiled.

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Translation methods
Method	Typical behaviour	What to remember
Compilation	Translates a source program into another representation before the resulting program runs.	C implementations commonly compile source to native code.
Interpretation	Executes a representation of the program through another program.	A language may have more than one implementation strategy.

Key points

Machine code is processor-specific.
An assembler translates assembly; a compiler can translate C.

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