Learning Aim A

Devices & Peripherals | Software & System Choice

Devices & Peripherals

Input Devices

Keyboard

Uses:

  • Text input
  • Command entry
  • Data typing

Advantages:

  • Accurate typing
  • Fast data entry
  • Large keys easy to use

Disadvantages:

  • Requires flat surface
  • Not portable
  • Limited for GUI navigation

Mouse

Uses:

  • Pointer control
  • Menu navigation
  • Icon selection

Advantages:

  • Precise control
  • Intuitive use
  • Supports GUI

Disadvantages:

  • Requires space
  • Cable limitation
  • Can cause RSI

More Input Devices

Touchpad

  • Portable: Built into laptops
  • No space needed: Compact design
  • Responsive: Gesture control
  • Downside: Smaller, less precise

Scanner

  • Digitizes: Converts paper to digital
  • OCR: Can recognize text
  • Quality: DPI affects resolution
  • Speed: Slower than typing

Touchscreen

  • Direct input: Tap to interact
  • Intuitive: Natural for users
  • Portable: Mobile/tablet use
  • Limitation: No multi-tasking easily

Microphone

  • Audio input: Voice commands
  • Recording: Podcasts, calls
  • Hands-free: Accessibility benefit
  • Background noise: Poor in noisy areas

Output Devices

Monitor / Display

Features:

  • Screen quality critical
  • Resolution matters (pixels)
  • Refresh rate for gaming
  • Color accuracy important

Types:

  • LCD (energy efficient)
  • OLED (better colors)
  • Curved (immersive)

Printer

Types:

  • Inkjet: Color, slow, cheap
  • Laser: Fast, monochrome, expensive
  • 3D: Objects, specialized

Considerations:

  • Cost per page
  • Speed (pages/min)
  • Quality needed

Speaker / Headphones

  • Speaker: Shared audio output
  • Headphones: Personal audio
  • Surround sound: Multiple speakers
  • Wireless: Bluetooth option
  • Quality: Frequency range matters

Projector

  • Large display: Presentations
  • Group viewing: Multiple people
  • Brightness: Lumens important
  • Resolution: 1080p, 4K
  • Placement: Throw distance

Storage Devices — Permanent Storage

Hard Drive (HDD)

How it works:

  • Spinning magnetic disk
  • Read/write head moves
  • Mechanical components

Advantages:

  • Large capacity
  • Low cost
  • Reliable for storage

Disadvantages:

  • Slower access
  • Moving parts fail
  • Fragile if dropped

Solid State Drive (SSD)

How it works:

  • No moving parts
  • Flash memory chips
  • Instant access

Advantages:

  • Very fast access
  • More reliable
  • Durable

Disadvantages:

  • More expensive
  • Lower capacity options
  • Can wear out

HDD vs SSD Comparison Table

Feature HDD SSD
Technology Magnetic spinning disk Flash memory chips
Speed Slower (200-300 MB/s) Faster (500-3000 MB/s)
Cost Cheaper More expensive
Reliability Moving parts fail No moving parts
Capacity Higher (4TB+) Growing (2TB common)
Best for Storage, archives OS, programs, gaming
Scenario: A video production company needs to store 10TB of raw footage. They should use HDDs for cost-effectiveness. But they also want the editing software on fast storage for quick response times, so they add an SSD for the operating system and applications.

USB Flash Drive

  • Portable: Pocket-sized
  • Universal: Works on any computer
  • Capacity: 32GB–1TB typical
  • Speed: USB 2.0 vs USB 3.0
  • Loss risk: Easy to misplace

Optical Media (CD/DVD/Blu-ray)

  • CD: 700MB capacity
  • DVD: 4.7GB capacity
  • Blu-ray: 25GB+ capacity
  • Uses: Archival, distribution
  • Downside: Can degrade over time

Temporary Storage (Memory)

RAM (Random Access Memory)

Purpose:

  • Temporary data storage
  • Currently running programs
  • Working data during processing

Key Facts:

  • Fast: Much faster than HDD
  • Volatile: Data lost when powered off
  • More RAM: Better multitasking
  • Typical: 8GB, 16GB, 32GB

Cache Memory

Purpose:

  • Extremely fast temporary storage
  • Between CPU and RAM
  • Stores frequently used data

Key Facts:

  • Fastest: Nanosecond access
  • Small: Usually 8MB–20MB
  • Expensive: High cost per MB
  • L1, L2, L3: Different levels

RAM vs Cache Comparison

Aspect RAM Cache
Speed Nanoseconds Sub-nanoseconds
Size GigaBytes (8-32GB) MegaBytes (8-20MB)
Cost Moderate Very expensive per byte
Volatile Yes Yes
Location Separate chip On CPU chip
Scenario: A graphics designer opens Photoshop with a 500MB image. The OS loads in RAM (2GB used). The CPU uses cache to temporarily store pixel data it's processing. With more RAM, the system won't need to swap to disk, keeping everything fast.

Processing Power

  • CPU speed (GHz)
  • Number of cores
  • Cache memory
  • Task execution speed

Memory & Storage

  • RAM capacity
  • Storage capacity
  • Speed of access
  • Data retention

A1.3 Drawing Skills: Flowcharts & System Diagrams

How to Draw a Flowchart (Exam Method)

  1. Read the scenario and identify the exact process sequence first.
  2. Use a Start and End terminal.
  3. Use input/output for data entry or display steps.
  4. Use process for actions (calculate, store, update).
  5. Use decision diamonds for yes/no checks and label branches.
  6. Keep arrows flowing top-to-bottom where possible to stay clear and readable.

Flowchart Symbols (Drawn)

Start / End
Terminal: Start or finish point.
Process
Process: An action or operation.
Input / Output
Input/Output: Data entered or shown.
Decision
Decision: A yes/no branch point.
A
Connector: Continue flow in another location.

Worked Flowchart Example (Login Check)

Login Validation Flowchart (Exam Example) Start Enter username and password Validate credentials Credentials correct? Open dashboard Show error + retry End Yes No Retry loop to input

How to Draw a System Diagram (Exam Method)

  1. List all components first: input devices, processing unit, storage, output devices, and network/cloud if used.
  2. Draw each component as a clear labeled box.
  3. Add arrows to show data flow direction between components.
  4. Label important links (for example: Wi-Fi, Ethernet, USB, HTTPS, VPN).
  5. Match your diagram directly to the scenario, not a generic setup.
Office System Diagram (Exam Example) Solid = wired, dotted = wireless Cloud Switch Core node Admin PC Keyboard + mouse Laser Printer Output File Server SSD storage Wi-Fi Router Gateway Staff Laptop Wireless client Wired link Wireless link Ethernet Print jobs File read/write Wi-Fi WAN uplink
Diagram Example: School office workstation — keyboard and scanner send data to CPU/RAM; files save to SSD; reports print to laser printer; encrypted backup syncs to cloud storage.

A1.3 Exam Checklist

Key definitions you must know

How to get full marks on a flowchart

  • Use the correct symbols throughout.
  • Include a clear start and end.
  • Show every important stage in the process.
  • Use labelled Yes/No branches at decision points.
  • Keep the logic in the right order.
  • Make arrows clear and unambiguous.

How to get full marks on a network diagram

  • Use standard symbols, not freehand sketches.
  • Show all key devices in the scenario.
  • Connect devices in the correct topology, usually star.
  • Show the router/switch link clearly.
  • Label devices so the examiner can identify them.
  • Use clear layout and avoid crossing lines where possible.

Typical exam question patterns

Common mistakes: Using the wrong shapes, missing the decision diamond, forgetting Yes/No labels, drawing freehand boxes instead of a network layout, or connecting devices in a confusing way.

Software & System Choice

Operating Systems

Software Applications

Factors When Choosing Devices & Software