Unit II: Number System, OS, and Programming Tools
Course: Fundamentals of Information Technology
Code: CAIDC101
Table of Contents
Number System and Codes
Number systems are used to represent numbers and characters in a computer-readable format.
Common Number Systems
- Binary: Base-2 system using only 0 and 1.
- Octal: Base-8 system using digits 0 to 7.
- Hexadecimal: Base-16 system using digits 0-9 and letters A-F.
- Conversion of Bases: The process of changing a number from one base (e.g., Decimal) to another (e.g., Binary).
Computer Character Codes
- BCD (Binary Coded Decimal): Represents each decimal digit by a 4-bit binary code.
- ASCII: Standard 7-bit or 8-bit code for representing characters.
- EBCDIC: 8-bit character encoding used primarily on IBM mainframes.
- Gray Codes: A binary system where two successive values differ in only one bit position.
Operating System: Basics and Functions
Operating System: A system software that manages computer hardware, software resources, and provides common services for computer programs.
Functions of an Operating System
- Memory Management: Allocating and de-allocating memory space.
- Processor Management: Deciding which process gets the processor when and for how much time.
- Device Management: Managing device communication via their respective drivers.
- File Management: Keeping track of information, location, uses, and status of files.
Types and Overview of Operating Systems
Operating systems are categorized based on their processing capabilities.
Windows and Linux Overview
- Windows: A proprietary graphical operating system developed by Microsoft.
- Linux: An open-source operating system known for its security and CLI (Command Line Interface).
- Differences: Windows is typically user-friendly for beginners (GUI focus), while Linux is highly customizable and preferred for servers.
Programming Language Tools
These tools are essential for translating human-readable code into machine language.
| Tool | Description |
|---|---|
| Assembler | Translates assembly language programs into machine code. |
| Compiler | Translates the entire high-level source code into machine code at once. |
| Interpreter | Translates high-level source code into machine code line by line. |
| Linker | Combines multiple object files generated by the compiler into a single executable file. |
| Loader | Loads the executable program into the main memory for execution. |
Algorithms and Flowcharts
- Algorithm: A step-by-step logical procedure to solve a specific problem.
- Pseudo-code: An informal, high-level description of an algorithm using plain English mixed with programming logic.
- Flowchart: A graphical representation of the sequence of operations in an information system or program.
- Computer Programs: The final implementation of algorithms in a specific programming language.
Exam Focus & Tips
- Exam Tip: Be prepared to differentiate between Compilers and Interpreters; this is a frequent question.
- Common Mistake: Confusing Binary (Base 2) with BCD. Remember BCD specifically maps decimal digits.
- Mnemonic: "ACL" for translation tools - Assembler, Compiler, Linker.
Frequently Asked Questions
Q: What is a Gray code used for?
A: It is often used in digital communications and error correction because only one bit changes at a time.
Q: What is the main role of a Linker?
A: To link object modules together to form a complete executable program.