O Levels & IGCSE Computer Science Notes

A set of flashcards based on the comprehensive notes covering key concepts in Computer Science for O Levels and IGCSE.

What is the primary purpose of the binary system in computer systems?

To process and store data using logic gates and transistors.

How do denary, binary, and hexadecimal differ in their base systems?

Denary is base 10, binary is base 2, hexadecimal is base 16.

What is one major benefit of using hexadecimal representation?

Hexadecimal uses fewer digits for the same value compared to binary.

What are the two methods for converting denary to binary?

Subtracting with the largest possible power of 2 and successive division by 2.

What happens during the binary addition overflow concept?

An overflow error occurs when the result exceeds the maximum value that can be stored.

What do logical binary shifts do?

Shift bits left or right, effectively multiplying or dividing the binary number by powers of 2.

What does Two’s Complement represent?

Negative binary numbers in binary form.

What is an ASCII character set?

A character set that assigns unique decimal values to characters and symbols.

What is the role of an ADC in sound wave processing?

To convert sound waves into digital data.

What are the differences between lossy and lossless file compression?

Lossy compression removes data permanently, while lossless compression allows original data to be reconstructed.

What is the purpose of data packets in data transmission?

To break down information into manageable pieces for easier transmission over networks.

What does the DNS do in relation to URLs?

It translates domain names into IP addresses.

How does HTTP differ from HTTPS?

HTTPS includes security features to protect data during transmission.

What is a MAC address?

A unique identifier for network interfaces used in communications on networks.

What is the function of the Control Unit in the CPU?

To manage the execution of instructions and control the flow of data within the CPU.

What is the Fetch-Decode-Execute cycle?

The process in which the CPU retrieves an instruction from memory, decodes it, and executes it.

What is the main function of an operating system?

To allow users to interact with the computer and manage hardware resources.

What distinguishes high-level programming languages from low-level languages?

High-level languages are closer to human language and easier to read; low-level languages provide more control over hardware.

What is an expert system in AI?

An AI designed to mimic human knowledge and solve complex problems based on a set of rules.

What is machine learning in AI?

The capability of a machine to learn from data and improve its performance over time.

What role do sensors play in automated systems?

They collect data from the environment and send it to the microprocessor for processing.

What are the advantages of using robotic systems in agriculture?

Increased efficiency, reduced labor costs, and more accurate cultivation practices.