Computer Systems Overview

Study Notes

CPU is the brain of the computer, responsible for processing instructions.
Input/Output (I/O) devices allow the computer to communicate with the outside world (e.g., keyboard, mouse, printer).
Evolution of computers has progressed from large mainframes to personal computers and mobile devices.

Data refers to raw facts and figures; information is processed data that is meaningful.
Types of data include text, numbers, images, and sounds.

Main components include CPU, memory, storage, input devices, and output devices.
Interconnections between components allow them to communicate and function together.

Memory is categorized as primary (RAM), cache, and secondary (hard drives, SSDs).
Units of memory are measured in bytes (KB, MB, GB).

A microprocessor is a compact integrated circuit that performs the functions of a CPU.
Evolution from simple processors to multi-core and high-speed processors.

Software is a collection of programs that instruct the computer on what to do.
Types:
- System software manages hardware and system resources (e.g., operating systems).
- Application software serves specific user tasks (e.g., word processors, games).
- Language translators convert high-level programming languages into machine code.

High-Level languages are user-friendly and resemble human languages (e.g., Python, Java).
Machine language consists of binary code that the computer can directly execute.

An OS is essential for managing computer hardware and software resources.
Functions of an OS include process management, memory management, and file management.

Decimal is base 10, Binary is base 2, Octal is base 8, and Hexadecimal is base 16.
Conversion involves changing a number from one system to another.

AI enables machines to simulate human intelligence.
Machine learning is a subset of AI, allowing systems to learn from data.
Natural Language Processing (NLP) enables computers to understand human language.
Robotics involves designing machines that can perform tasks autonomously.
Big Data refers to large, complex data sets that require advanced processing methods.
IoT connects everyday devices to the internet for smarter functionality.
Sensors are devices that detect and respond to environmental changes.
Smart Cities use technology to enhance urban living.
Cloud Computing allows storage and access of data over the internet.
Grid Computing uses a network of computers to work on shared tasks.
Blockchain technology provides secure, decentralized record-keeping.
5G Network offers faster internet connectivity and lower latency.
E-Commerce involves online buying and selling of goods and services.

The problem-solving cycle consists of analyzing the problem, designing algorithms, coding, and testing solutions.
An algorithm is a step-by-step procedure for solving a problem.
Flowcharts visually represent algorithms and processes.

Constructs include sequence (step-by-step execution), selection (conditional branching), and iteration (repetition).
Common selection statements are if, if-else, and nested if.

Python is a popular programming language known for its simplicity and versatility.
Welcomes both interactive mode (user inputs commands directly) and script mode (running complete programs).
Basic elements include identifiers, keywords, constants, variables, and data types.

Control structures dictate the flow of execution.
Sequencing executes statements linearly, selection decides paths, and repetition loops through code.

Functions are reusable pieces of code that perform specific tasks.
User-defined functions are created by the programmer, while built-in functions are provided by the language.

Strings are sequences of characters, with operations for initialization and access.
Lists store multiple items and allow for manipulation such as creation, initialization, and traversal.

Digital footprints are traces left by users online, requiring responsible online behavior.
IPR protects creators' rights, while cyber laws address online crimes like hacking and phishing.
Cyberbullying is a serious issue that can have real-world consequences.

Prolonged technology use can lead to health issues such as eye strain and physical inactivity.
Awareness and moderation are essential for healthy technology usage.