Computer science definitions

Decomposition

Breaking down a large problem into a smaller probelm

Why do decomposition

Smaller problems are easier to solve. Can be tested independently

Abstraction

Removing unnecessary details to focus on important features

Subprogram

Out of line block of code that may be called by simply writing their name

Benefits of subprogram

Makes big problems easier to break down. Allows different team members to work on different parts of the project. Easier to debug. More efficient as code is not duplicated.

Algorithm

A precise set of rules or instructions to solve a specific problem or task

Pseudocode

Text-based tool that uses short English words to describe an algorithm.

RAID

Redundant Array of Independent Discs

RAID purpose:

Protect against data loss by creating copies of data on different drivers

Quid pro quo

Where an attacker gives the victim a service or benefit in exchange for personal information

Worm

Malicious code that makes copies of itself and does harm to the users computer. Works by itself. Does not need to attach to a computer program like a virus

Baiting

Attackers use a lure such as free downloads to get the user to install malicious software or divulge sensitive information

Why encrypt on internet

So hackers can’t understand the data transmission. Scrambles it into an unreadable format of cyphertext

Phishing

Criminals impersonate a trustworthy entity to trick users into divulging personal or sensitive information

Data compression

Reducing a file size for efficient storage and transmission

Bit

1 or 0. smallest block of data

Lossy compression

File size is decreased. Data is lost. Non-reversible. Less storage space. Easier to store and transfer

Compiler

Translates the high-level code into machine code all in one go. Original source code is not shared. When shared does not need a translator. Optimises. Memory intensive

Interpreter

Translate high-level languages to machine code one line at a time. Good for debugging. Slower. No optimisation.

High-level programming language

English-like statements. Needs to be translated before running. One line of code does multiple operations. Easy to write and debug

Low-level language

One line of code is one machine operation. Used to write base operating systems (device drivers, operating system kernsl) Direct control over hardware. Written for specific processors

Machine code

Binary or hexadecimal. Understood by computer.