Computer Knowledge and Information Technology
Computer knowledge here is basic but broad: hardware and memory, operating systems, MS Office, internet and networking, and cyber crime with the IT Act, 2000. Questions are definitional, so precise terms earn the marks.
Core facts
- 1 byte = 8 bits; 1 KB = 1024 bytes, 1 MB = 1024 KB, 1 GB = 1024 MB, 1 TB = 1024 GB.
- RAM is volatile, ROM is non-volatile; cache is the fastest memory; registers sit inside the CPU.
- An operating system manages processes, memory, files and devices - Windows, Linux, Android.
- Shortcuts: Ctrl+C/V/X/Z/Y, Ctrl+S, Alt+Tab, F2 rename, Ctrl+Shift+Esc for Task Manager.
- Networking: IP address, DNS, HTTP and HTTPS (port 443), LAN and WAN, firewall; SMTP sends mail while POP3 and IMAP receive it.
- IT Act, 2000: section 66C identity theft, 66D cheating by impersonation, 66E privacy violation, 66F cyber terrorism, 67 obscene material. Report financial cyber fraud on 1930 or cybercrime.gov.in.
Worked example
How many 4 MB photographs fit in a 2 GB pen drive? Reasoning: 2 GB = 2 × 1024 MB = 2048 MB. Dividing by 4 MB per photograph gives 512. Answer: 512 photographs.
Traps
- Using 1000 instead of 1024 for storage units.
- Confusing phishing (fake email or link) with pharming (DNS redirection).
- Calling ROM volatile.
- Swapping SMTP with receiving protocols.
- Forgetting that HTTPS encrypts traffic and HTTP does not.