Fundamentals of Computer Systems

What Fundamentals of Computer Systems covers

Hardware and software and how software is classified, programming languages and their translators, logic gates and Boolean algebra. Examined on Paper 2.

The 9 subtopics

Each one has its own page.

• Hardware, Software and Its ClassificationRecall questions on the definitions of hardware and software, the relationship between them and the classification of software.Open →
• System Software and the Operating SystemRecall questions on the four types of system software, the need for an operating system, its main functions and the role of utility programs.Open →
• Translators and the Role of the Operating SystemRecall questions on the functions of an assembler, a compiler and an interpreter, and on how an operating system shields users from the hardware.Open →
• Classification of programming languagesRecall questions on machine code and assembly language, what makes a language low level, and the advantages and drawbacks of low-level programming.Open →
• Types of program translatorRecall questions on assemblers, compilers and interpreters, when each is the right choice, and why some compilers emit bytecode for a virtual machine.Open →
• Logic Gates and Their Truth TablesRecall questions on the truth tables of the NOT, AND, OR, XOR, NAND and NOR gates.Open →
• Logic Circuits and D-Type Flip-FlopsRecall questions on interpreting logic circuits, completing truth tables, drawing circuits for Boolean expressions, and what the edge-triggered D-type flip-flop is, how it is drawn and what it stores.Open →
• Half-Adders and Full AddersRecall questions on the half-adder's circuit and truth table, its limitation, building a full adder from two half-adders, tracing both for given inputs, and chaining full adders to add eight-bit numbers.Open →
• Boolean algebraRecall questions on the identities and the commutative, associative, distributive and absorption laws, De Morgan's laws, and simplifying an expression step by step.Open →

What you need to know

Answer each one before you reveal it.

Take Fundamentals of Computer Systems further

The same content, four other ways.

Commonly confused

Pairs that lose marks when they are blurred together.

• Compiler vs Interpreter

  Compiler: a translator normally processing a whole high-level program. Interpreter: a translator executing source statements one at a time.

• Source code vs Object code

  Source code: instructions written in the original programming language. Object code: translated machine-level instructions produced from a source program.

• High-level language vs Low-level language

  High-level language: instructions designed for human readability and portability. Low-level language: instructions closely reflecting processor operations.

Questions from this topic

Each one with the model answer underneath.

1. 1

   Define hardware.

   Model answer

   Hardware is the physical, tangible parts of a computer system: the electronic and mechanical components you could touch, such as the processor, main memory, motherboard, hard disk, keyboard, monitor and the cables and circuitry that connect them.

2. 2

   Define software.

   Model answer

   Software is the collection of programs and the associated data that run on the hardware. It is not physical: it is sequences of instructions, stored as binary machine code, that tell the hardware what to do. Examples include an operating system, a word processor, a compiler and a games engine.

3. 3

   Explain the relationship between hardware and software.

   Model answer

   They are interdependent and neither is useful alone. Hardware without software is inert: general-purpose electronics with no instructions to follow. Software without hardware cannot run: it is only a stored pattern of bits until a processor fetches and executes it. Software is written to control and exploit the hardware, and the hardware is designed to be capable of executing the instructions software is made from. Software is loaded into main memory as machine code and the processor's hardware carries those instructions out.

4. 4

   Why can a computer's function be changed without changing any of its physical parts?

   Model answer

   Because the machine is general purpose: its behaviour is determined by the program stored in memory rather than by its wiring. Loading a different program changes what the same hardware does, so one machine can be a word processor, a games console and a web server on different occasions.

5. 5

   Is firmware hardware or software, and why is it easy to confuse the two?

   Model answer

   Firmware is software: it is a program, held permanently in read-only or flash memory on a hardware component. It is confused with hardware because it is supplied inside the physical device and is not normally changed by the user, but it is still a set of instructions rather than a physical part.

6. 6

   A student says a printer driver is hardware because it makes the printer work. Correct them.

   Model answer

   A driver is software. It is a program that translates general requests from the operating system into the specific commands and signals the particular printer understands. The printer itself, and the port and cable, are the hardware; the driver is a set of instructions that controls them.

What is inside Levo

Six ways to work the same material.

Fundamentals of Computer Systems revision questions

What does Fundamentals of Computer Systems cover in AQA A-Level Computer Science?

9 subtopics: hardware, software and its classification, system software and the operating system, translators and the role of the operating system, classification of programming languages, types of program translator, logic gates and their truth tables, logic circuits and d-type flip-flops, half-adders and full adders and boolean algebra. Each one has its own page with questions and model answers.

How is Fundamentals of Computer Systems organised?

By the AQA 7517 specification, subtopic by subtopic, so it matches the order you are taught it in.