Basic Computer Knowledge
Basic Computer Knowledge checks everyday computer literacy: hardware and software, memory and storage, operating-system basics, MS Word, Excel and PowerPoint, internet and email, networking, and safety and security. Questions are definitional and shortcut-based, so recall is enough.
Core rules
- CPU = ALU + control unit + registers; primary memory is RAM (volatile) and ROM (non-volatile); secondary storage is HDD, SSD or pen drive.
- Storage units: 8 bits = 1 byte; 1 KB = 1024 B; 1 MB = 1024 KB; 1 GB = 1024 MB; 1 TB = 1024 GB.
- Shortcuts: Ctrl+C copy, Ctrl+X cut, Ctrl+V paste, Ctrl+Z undo, Ctrl+Y redo, Ctrl+S save, Ctrl+P print, F2 rename, F5 refresh.
- Excel: every formula starts with '='; A1 is a cell reference; SUM, AVERAGE, COUNT and IF are common functions; the $ sign makes a reference absolute.
- Internet: an IP address identifies a device, HTTP/HTTPS is the web protocol, a URL is an address, and a browser renders pages; a LAN is local while a WAN spans large distances.
- Threats: virus, worm, trojan and phishing; a firewall and updated antivirus are the basic defences.
Worked example
Convert binary 1101 to decimal. Write the place values 8, 4, 2, 1 and multiply each by its bit: 1×8 + 1×4 + 0×2 + 1×1 = 8 + 4 + 0 + 1 = 13. Checking by repeated division of 13 by 2 gives remainders 1, 0, 1, 1, that is 1101, confirming the answer.
Traps
- Using 1000 instead of 1024 when converting memory units.
- Calling RAM non-volatile, or confusing memory with storage capacity.
- Reading Ctrl+Z as cut instead of undo.
- Assuming any web page is secure; HTTPS is the indicator to check.