Information Technology (Intermediate Matriculation)
This section covers the MATSEC Intermediate Matriculation Information Technology syllabus. It tests core IT theory: data representation, computer architecture, software, networks, databases and spreadsheets, algorithm design, system development, and security and social issues around ICT. Questions reward precise definitions, correct conversions and short applied reasoning rather than long code.
Core rules and concepts
- A bit is one binary digit; a nibble is 4 bits; a byte is 8 bits. Memory multiples are binary: 1 KiB = 1024 bytes and 1 MiB = 1024 KiB; SI kB = 1000 bytes.
- Bases: binary (2), denary (10), hexadecimal (16, digits 0–9 and A–F). One hex digit maps to four bits, so hex is compact binary shorthand.
- Two's complement for n bits covers −2^(n−1) to 2^(n−1)−1; negate by inverting every bit and adding 1.
- ASCII is 7-bit (128 codes; extended 8-bit forms exist); Unicode covers multilingual scripts.
- Gates: AND, OR, NOT, NAND, NOR, XOR. An n-input truth table has 2^n rows.
- Databases: entity/table, attribute/field, record; the primary key uniquely identifies a record, a foreign key references another table's primary key, and normalisation reduces redundancy.
- Spreadsheets: relative references (A1) shift when copied; absolute references ($A$1) do not.
- Networks: LAN versus WAN; IP addresses and DNS; star topology; protocols TCP/IP, HTTP(S), SMTP.
- SDLC: analysis, design, implementation, testing, maintenance; waterfall is sequential, iterative models loop.
- Security: malware, phishing, firewalls, encryption, backups, data protection principles.
Worked example
Convert denary 45 to binary and hex, then give −45 in 8-bit two's complement. Place values 32 + 8 + 4 + 1 give 101101; padded to 8 bits, 00101101. Grouping 0010 1101 gives hex 2D. For −45, invert 00101101 to 11010010, add 1 → 11010011; the leading 1 confirms a negative value.
Traps that cost marks
- Mixing kB (1000 bytes) with KiB (1024 bytes).
- Taking two's complement without padding to the stated bit width, so the sign bit is wrong.
- Reversing primary and foreign keys: a foreign key may repeat or be null; a primary key cannot.
- Copying a formula and assuming A1 stays fixed instead of writing $A$1.
- Treating JPEG or MP3 compression as lossless.