Hardware and Software Fundamentals
Hardware concepts
Candidates must describe the function of the CPU (fetch-decode-execute cycle), RAM (volatile working memory), ROM and flash (non-volatile storage of firmware), secondary storage (HDD, SSD, optical, cloud), motherboards, buses and peripherals. Understand the input-process-output-storage model and be able to trace a simple operation through it. Know the trade-offs: SSD versus HDD (speed and shock resistance versus cost per gigabyte and capacity), RAM versus storage (volatile working space versus persistent data), and integrated versus dedicated graphics.
Software concepts
Distinguish system software (operating systems, utilities, drivers) from application software (productivity suites, browsers, games). Know the operating system's roles: process and memory management, file management, device management, user interface provision and security. Compare proprietary, open-source, freeware and subscription licensing, and the difference between locally installed and cloud-hosted (SaaS) software.
Traps in questions
- Saying more RAM makes a computer faster in all cases; it improves multitasking until the working set fits, then gains flatten.
- Confusing ROM with RAM, or claiming flash is volatile.
- Describing an operating system as application software.
- Ignoring compatibility: drivers, file formats, and hardware requirements for software.
- Mixing up a file extension with a file format, or a codec with a container.
Worked rule of thumb
Choose hardware by matching the bottleneck to the workload. Video editing is bound by CPU cores, GPU acceleration and fast scratch storage, so prioritise those; office work is bound by RAM and SSD responsiveness. State the workload, identify the bottleneck, then justify the component.
Maintenance and accessibility
Include updates, backups, antivirus, and ergonomic or accessibility considerations such as screen readers, alternative input devices and adjustable displays.