Computer and Information Technology
IT questions in this paper are practical: number systems, hardware versus software, memory units, operating systems, office shortcuts, networking basics, and the e-government systems a Preventive Officer actually touches.
Facts to hold
- 1 byte = 8 bits; 1 KB = 1024 bytes; 1 MB = 1024 KB; 1 GB = 1024 MB; 1 TB = 1024 GB.
- The CPU contains the arithmetic logic unit, control unit and registers; RAM is volatile, ROM is not.
- Banking cheques use MICR; answer sheets use OMR; barcodes use optical scanning.
- Shortcuts: Ctrl+C copy, Ctrl+X cut, Ctrl+V paste, Ctrl+Z undo, Ctrl+Y redo, Ctrl+S save, Ctrl+F find, Ctrl+P print, Alt+Tab switch windows.
- Networking: LAN versus WAN, IP addressing, HTTP versus HTTPS, and the role of a firewall.
- Pakistani e-government: NADRA CNIC verification, FBR's IRIS portal for e-filing returns, and Pakistan Customs' WeBOC and, increasingly, the Pakistan Single Window for cross-border trade.
Worked example
Convert decimal 25 to binary. Divide repeatedly by 2 and record remainders: 25 gives 12 remainder 1; 12 gives 6 remainder 0; 6 gives 3 remainder 0; 3 gives 1 remainder 1; 1 gives 0 remainder 1. Read the remainders bottom-up: 11001. Check by place value: 16 + 8 + 1 = 25.
Traps
Using 1000 instead of 1024 for KB, MB and GB. Confusing 'Save' with 'Save As', or RAM with storage. Mixing up input and output devices - a touchscreen does both. Treating HTTPS as a different protocol rather than HTTP secured by TLS.