Notes, summaries, assignments, exams, and problems for Computers

File Management

File management is the system an operating system uses to organize and keep track of data. The operating system stores data in units called files, determines how files are stored, efficiently uses available storage space, creates a record of all file usage, and carries out every task related to files and folders.

File names typically have this structure:

filename.extension

Task and User Management

Task Management

Task management is the part of the operating system that controls the running of one or more programs on a computer simultaneously. Today's widely used operating systems support multitasking, allowing multiple tasks to run concurrently, taking turns using the computer's resources.

User Management

With user management, the operating... Continue reading "Understanding Operating Systems: File, Task, and User Management" »

A code in which each alphanumeric character is represented as a number from 0 to 127, translated into a 7-bit binary code for the computer. Binary

Assembly language: A programming language that is once removed from a computer's machine language. Machine languages consist entirely of numbers.

Availability:

A measure of how easy or difficult it is to obtain a piece of hardware or a computer application

Backbone:

High-speed lines or connections that form the major access pathways within the Internet.

Bandwidth:

The capacity of a networked connection

Banner:

The title of a printed document which identifies it.

Batch processing:

System of processing data in groups at the same time without requiring instructions from the users

Baud:

The unit for measuring the... Continue reading "ASCII Code: American Standard Code for Information Interchange" »

C++ Loops: While, Do-While, and For

While Loop Format

while (condition)
{
    statements(s);
}

How While Loop Works

If the condition is true, the statement(s) are evaluated again. If false, the loop is exited.

While Loop Example

int val = 5;
while (val >= 0)
{
    cout << val << " ";
    val = val - 1;
}

A while loop is a pretest loop (the condition is evaluated before the loop executes).

• If the condition is initially false, the statement(s) in the body of the loop are never executed.
• If the condition is initially true, the statement(s) in the body will continue to be executed until the condition becomes false.

The loop must contain code to allow the condition to eventually become false so the loop can be exited. Otherwise, you have... Continue reading "C++ Loops and File Handling: A Deep Dive" »

MapReduce is a computing paradigm for processing data that resides on hundreds of computers, which has been popularized recently by Google, Hadoop, and many others. The paradigm is extraordinarily powerful, but it does not provide a general solution to what many are calling “big data,” so while it works particularly well on some problems, some are more challenging. This book will teach you what problems are amenable to the MapReduce paradigm, as well as how to use it effectively. At first glance, many people do not realize that MapReduce is more of a framework than a tool. You have to fit your solution into the framework of map and reduce, which in some situations might be challenging. MapReduce is not a feature, but rather a constraint.... Continue reading "Understanding MapReduce Design Patterns" »

Python Fundamentals: Practical Code Examples

This document presents a collection of basic Python code snippets, demonstrating fundamental programming concepts such as conditional statements, loops, data input, and list manipulation. Each example is designed to illustrate a specific programming principle, making it ideal for beginners learning Python.

Compare Car Top Speeds with Python

This Python script compares two user-entered car speeds to determine which is faster, showcasing basic input and conditional logic.

car_a = int(input("Please enter the top speed of a Ferrari: "))
car_b = int(input("Please enter the top speed of a Lamborghini: "))

if car_a >= car_b:
    print("The fastest car is a Ferrari.")
elif car_b > car_a:
    print("The

BD 2C 3B D

John Cravern

B 3D C D A B

The End of the World Train

BD 2C 2B 2D

Slvalbart

C 2D 2B A B C

Save the Animals

BD C B A C B D

Michael Pallin

D A B C A D C A

Ruth Manorama

B A C 2D A C D

A Better World

BC B A C D B D

A Champion on Two

2B A C 2B B C

Butter and Bread

BD 2C 2B D C

A Journalism

DB A B 2C B A

Vegetarianism

CD 2B A B D A

Smiling Indians

CD BAC ACB

Norwich

BD CD CB DC

The Best Advice

AC AC BC DA

Interview with a Scriptwriter

3B 2C A B C

An Interview with a Champion

3B 2C D A C

ASCII Code

American Standard Code for Information Interchange. A code in which each alphanumeric character is represented as a number from 0 to 127, translated into a 7-bit binary code for the computer. ASCII is used by most microcomputers and printers, and because of this, text-only files can be transferred easily between different kinds of computers.

Availability

A measure of how easy or difficult it is to obtain a piece of hardware or a computer application.

Backbone

High-speed lines or connections that form the major access pathways within the Internet.

Bandwidth

The capacity of a networked connection. Bandwidth determines how much data can be sent along the networked wires. Bandwidth is particularly important for Internet connections, since greater... Continue reading "A Glossary of Computer and Internet Terms" »

Introducing Networks

A network is created when more than one device is connected together. A network can be a small collection of computers connected within a building (e.g. a school, business, or home) or it can be a wide collection of computers connected around the world.

Advantages

• Communication – it is easy (and often free) to communicate using email, text messages, voice calls, and video calls.
• Roaming – if information is stored on a network, it means users are not fixed to one place. They can use computers anywhere in the world to access their information.
• Sharing information – it is easy to share files and information over a network. Music and video files, for instance, can be stored on one device and shared across many computers, so

Application Software

System Software

Operating System

Why OS?

Operating System Function

OS Goals

Types of Operating Systems

• Single Process Operating System
• Batch-Processing Operating System
• Multiprogramming Operating System
• Multitasking Operating System
• Multi-Processing Operating System
• Distributed System
• Real Time OS

Program

Process

Thread

Multi-tasking vs Multi-Threading

Thread Scheduling

Thread Context Switching vs Process Context Switching

User Space

Kernel

Functions of Kernel

• Process Management
• Memory Management
• File Management
• I/O Management

Type Of Kernel

• Monolithic
• Micro
• Hybrid
• Nano

System Calls

Types

• Process Management
• Device Management
• File Management
• Information Management
• Communication Management

Firmware: SW embedded in HW (microprocessor -> microcontroller)

What