Hardware, CPU and Memory: Revision and References
Shared revision, practice questions, answer explanations and references from the original module.
By Akhilesh Saini
Consolidated module revision
| Exam clue | Answer to recall | Caution |
|---|---|---|
| Main circuit board | Motherboard | Not the same as CPU |
| Processor performing arithmetic | ALU | CU directs operations |
| Direct CPU working locations | Registers | Smaller/faster than RAM |
| Objective answer-sheet bubbles | OMR | Not OCR |
| Magnetic-ink cheque characters | MICR | Not barcode reader |
| Printed words recognized from scan | OCR | Scanner first captures image |
| Physical paper output | Hard copy | On-screen document is soft copy |
| Printer that strikes ribbon | Dot-matrix | Impact category |
| Printer that uses toner | Laser printer | Non-impact |
| Temporary active programs | RAM | Volatile |
| Frequently needed CPU data | Cache | Generally smaller than RAM |
| Persistent startup code | Firmware in non-volatile memory | Often updateable flash |
| Rotating magnetic platters | HDD | Not SSD |
| Non-volatile solid-state drive | SSD | Not the same as RAM |
| Laser-read disc | CD/DVD/Blu-ray | Optical storage |
| Eight bits | One byte | Capital B means byte |
| 1024 bytes exactly | One KiB | kB is decimal under SI |
| Digital monitor/TV connection | HDMI or DisplayPort | Exact support varies |
| Wired LAN connection | Ethernet | Not automatically internet |
| Reversible USB form | USB Type-C | Feature support varies |
Mini self-check
Before moving to software and operating systems, make sure you can explain these three situations without guessing:
- A person scans a cheque, recognizes special magnetic-ink characters, processes the transaction and prints a receipt. Which stages use input, processing, storage and output?
- A program is saved on an SSD, opened in RAM, and worked on by the CPU. What information is likely to survive power-off, and what may be lost before saving?
- A 16-bit field stores how many bytes? Explain why a printed “16 GB” capacity and a system's GiB display may be numerically different even if neither is wrong.
Self-check guidance: In (1), recognition of MICR characters is input; processing follows; persistent transaction records require suitable storage; the printer gives hard-copy output. In (2), already saved SSD data persists, while unsaved RAM work may be lost. In (3), 16 bits are 2 bytes; GB is decimal and GiB is binary.
Sources and further reading
These references support the technical definitions and the accuracy cautions. The explanations and questions in this module are original educational writing.
- Intel — Motherboard anatomy and major components: CPU sockets, memory slots, expansion connections, chipset and I/O.
- IBM — Microprocessor components: ALU, control unit, registers, cache and instruction processing.
- IBM — Primary storage: RAM, ROM and cache concepts.
- IBM — HDD versus SSD: storage technologies and NVMe/PCIe distinctions.
- IBM — MICR recognition: historical and technical use of magnetic-ink cheque characters.
- NIST — Binary prefixes: exact distinction among kB, KiB, MB and MiB.
- NIST — SI prefixes: decimal and binary prefix families.
- USB-IF — Cables and connectors: cables with the same connector can have differing capabilities.
- SD Association — SD memory card standard overview: SD and microSD memory-card terminology.