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OGE Informatics study materials
OGE Informatics study resources

OGE Informatics: Computer Systems, Software, and File Organization

OGE Informatics · Work through your exam, one topic at a time.

All guide sections

Computer Systems, Software, and File Organization

Core ideas

Know the von Neumann architecture: CPU (ALU + control unit), memory, input/output, with the stored-program principle. Distinguish RAM (volatile, fast) from ROM and long-term storage. Software splits into system software (OS, drivers, utilities) and application software. Files are organized in a hierarchical file system with a root, directories, and a path; extensions indicate type (.txt, .exe, .jpg).

Traps to watch

  • Calling an operating system "application software" - it is system software.
  • Confusing RAM (temporary, cleared on power-off) with permanent storage.
  • Misreading a full path: C:\docs\work\a.txt - the file is a.txt, the folder is work, the drive is C:.
  • Wildcards: * matches any number of characters, ? matches exactly one. *.doc matches report.doc but not report.docx.
  • Confusing an extension with the file name.

Rule of thumb

For path questions, split on the separator and read right-to-left: last element = file, previous = its folder, first = drive/root. For wildcards, count characters matched by ? exactly.

Worked example

Which files match ?a*.txt? Candidates: map.txt (m,a → yes), a.txt (needs one char before a → no), data.txt (d,a → yes). The ? requires exactly one leading character, and * allows any remainder before .txt.