Operating Systems and Utility Software
What this domain covers
The exam checks that you can name the functions of an operating system, distinguish OS types, and choose the right utility for a job such as defragmentation, backup, antivirus scanning, compression or disk cleanup.
Core rules
- OS duties: process management, memory management, file management, device management through drivers, security, and the user interface (GUI or CLI).
- Types include single-user and multi-user, single-tasking and multitasking, batch, time-sharing and real-time, where deadlines must be met.
- Booting runs firmware (BIOS/UEFI), then POST, then the bootloader, then the kernel. Safe Mode loads minimal drivers for troubleshooting.
- Virtual memory uses a page file on disk when RAM is full; it prevents crashes but is far slower than RAM.
- File-system limits matter: FAT32 caps a single file at 4 GB, while NTFS and exFAT do not. Defragmentation helps magnetic HDDs, not SSDs.
Worked example
A student tries to copy a 6 GB video onto a 32 GB pen drive formatted FAT32 and gets "file too large". Reasoning: the drive has space, so capacity is not the problem; the 4 GB per-file limit of FAT32 is. Fix: back up the contents, reformat as exFAT (or NTFS if the drive is used mainly on Windows), then copy again.
Traps
- Saying formatting "cleans" a disk; formatting destroys the file table and the data.
- Recommending defragmentation for an SSD instead of TRIM.
- Confusing a utility such as an antivirus or archiver with the operating system itself.