Computer Science P1 Flashcards
What does the ALU do in a CPU?
Arithmetic Logic Unit - performs calculations and logical operations.
What is the purpose of the Control Unit?
Fetches, decodes, and executes instructions. Manages hardware via control signals.
What is Von Neumann architecture?
Stored program concept where data and instructions are stored in memory.
What affects CPU performance?
Clock speed, cache size, number of cores, and RAM speed.
What is the purpose of registers?
Tiny, high-speed memory locations in the CPU (e.g., PC, MAR, MDR).
What’s the difference between RAM and ROM?
RAM is volatile read/write memory; ROM is non-volatile read-only memory.
Why is virtual memory used?
Allows running large programs by using secondary storage as temporary RAM.
What are the 3 main types of secondary storage?
Magnetic (HDD), Solid State (SSD), Optical (CD/DVD/Blu-ray).
What are characteristics of SSDs vs HDDs?
SSD: faster, no moving parts, more expensive. HDD: cheaper, slower, mechanical.
What is a network protocol?
Rules governing data transmission between devices (e.g., TCP/IP, HTTP).
What’s the difference between LAN and WAN?
LAN covers small geographical area; WAN covers large areas (e.g., internet).
What is a star topology?
All devices connect to a central switch/router. Benefits: reliable, high performance.
What is a mesh topology?
Devices connect to multiple others. Benefits: redundancy, self-healing.
What does TCP/IP do?
Transmission Control Protocol/Internet Protocol - governs data packet delivery.
What is HTTP vs HTTPS?
Hypertext Transfer Protocol (unsecure) vs encrypted version using SSL/TLS.
What are 4 common network threats?
Malware, phishing, DDoS attacks, SQL injection.
How does a firewall improve security?
Monitors incoming/outgoing traffic and blocks unauthorized access.
What is encryption?
Scrambling data to make it unreadable without a decryption key.
What is a MAC address?
Unique identifier assigned to network interfaces (physical address).
What is an IP address?
Logical address assigned to devices on a network (IPv4 or IPv6).
What is the purpose of DNS?
Domain Name System - translates domain names to IP addresses.
What are the main OS functions?
Memory management, file management, hardware control, user interface.
What is utility software?
Programs that maintain system (e.g., antivirus, disk defragmenters, backups).
What is open source vs proprietary software?
Open source: code modifiable/free. Proprietary: paid, restricted code.
What is the Data Protection Act 2018?
UK law governing personal data storage and processing (GDPR implementation).
What is a brute force attack?
Trying all password combinations to gain unauthorized access.
What is a syntax error?
Code that violates language rules (e.g., missing colon in Python).
What is a logic error?
Program runs but produces incorrect results due to flawed logic.
What is the purpose of an IDE?
Integrated Development Environment - tools for writing/testing code (debugger, editor).
What is abstraction?
Simplifying complex systems by focusing on key details while hiding complexity.
What is decomposition?
Breaking problems into smaller, manageable sub-problems.
What is binary search?
Efficient search algorithm requiring sorted data (divides search space in half).
What is linear search?
Checks each element sequentially until target is found.
How does bubble sort work?
Repeatedly compares/swaps adjacent elements until sorted.
What is a variable?
Named storage location that holds data which can change during execution.
What are the 3 basic programming constructs?
Sequence, selection (if/else), iteration (loops).
What is casting in programming?
Converting between data types (e.g., string to integer).
What is an array?
Data structure storing elements of the same type under one name.
What’s the difference between a compiler and interpreter?
Compiler: entire code translated at once. Interpreter: line-by-line execution.
What is file handling used for?
Reading from/writing to external files (e.g., .txt, .csv).
What is validation vs verification?
Validation: checks input follows rules. Verification: confirms data accuracy (e.g., double entry).
