Punjab PSEB Senior Secondary NSQF IT/ITeS cheat sheet
Punjab PSEB Senior Secondary NSQF IT/ITeS · Keep the key ideas within reach.
Information Technology / IT-enabled Services (NSQF) - Core Reference
NSQF level structure: the National Skills Qualifications Framework places vocational awards on levels 1–10; PSEB Senior Secondary vocational subjects sit at Level 4, aligned to class 11–12 schooling and entry-level industry roles.
IT-ITeS sector split: IT services (software development, testing, maintenance) versus IT-enabled services (BPO, KPO, data entry, technical helpdesk, digital marketing, GIS, medical transcription); the trade covers both, so exam items may use either label.
Hardware basics: CPU (ALU + control unit + registers) executes instructions; primary memory is RAM (volatile) and ROM (non-volatile); secondary storage includes HDD, SSD, and optical media; input devices convert physical data to digital signals, output devices do the reverse.
Number systems: binary base 2, octal base 8, decimal base 10, hexadecimal base 16; 1 byte = 8 bits, 1 KB = 1024 bytes, 1 MB = 1024 KB; convert decimal to binary by repeated division by 2 reading remainders bottom-up.
Software classes: system software (OS, device drivers, utilities) manages hardware; application software (word processor, spreadsheet, browser) serves user tasks; firmware is software embedded in hardware such as BIOS/UEFI.
Networking essentials: LAN covers a building, WAN spans cities/countries, topology may be star, bus, ring, or mesh; IPv4 addresses are 32-bit, IPv6 are 128-bit; TCP is connection-oriented and reliable, UDP is connectionless and faster.
OSI reference model has 7 layers (Physical, Data Link, Network, Transport, Session, Presentation, Application); TCP/IP model condenses these into 4 layers; routers operate at the network layer, switches at the data link layer.
Security fundamentals: authentication verifies identity, authorization grants permissions; malware types include virus, worm, trojan, ransomware, and spyware; a firewall filters traffic by rules and antivirus uses signatures plus heuristics.
Database basics: a DBMS stores related data in tables of rows (records) and columns (fields); primary key uniquely identifies a row, foreign key references another table's primary key; SQL commands split into DDL (CREATE, ALTER, DROP) and DML (SELECT, INSERT, UPDATE, DELETE).