IT2402 Basics of Programming

Programming Basics

• A computer program consists of a sequential set of instructions (code) written in a computer language to perform specific tasks.
• Examples of software types include system software, web browsers, utility software, multimedia software, and spreadsheet software.
• Instructions must be performed in a sequence unless specified otherwise.

Definition of Programming

• Programming is the art and science of instructing computers to perform tasks using a programming language.
• It allows for the creation of codes to solve problems, develop software applications, design websites, analyze data, and automate processes.
• Proficiency in programming leads to career opportunities in software development, web development, data science, and artificial intelligence.
• Enhances skills such as critical thinking, logical reasoning, and problem-solving.

Evolution and History of Programming

• Initially, programming involved writing machine code consisting of binary instructions (0 and 1).
• High-level programming languages emerged to simplify coding through human-readable syntax.
• A wide variety of programming languages and tools now exist to address various application domains and paradigms.

Programming Paradigms

• Procedural Programming: Focuses on reusable procedures/functions; emphasizes the sequence of steps. Common languages include BASIC, C, C++, Pascal, and Java.
• Object-Oriented Programming (OOP): Centers around objects encapsulating data and behavior, promoting modularity and code reusability. Examples are Python, VB.NET, and C#.
• Functional Programming: Treats computation as evaluating mathematical functions; values consistency and minimizes side effects.

Programming Languages

• Low-level Languages: Close to machine code; offers direct hardware control for precise execution. Examples include Assembly Language and Machine Language.
• High-level Languages: Easy for humans to read and write; abstracts hardware details. Examples include C++, Pascal, PHP, Python, and Java.
• Language choice depends on project requirements, performance needs, community support, and available libraries/frameworks.

Key Programming Terminologies

• Syntax: Rules defining valid combinations and arrangements in a programming language.
• Command: Unique instruction for tasks, e.g., "print" for displaying text.
• Integrated Development Environment (IDE): Software applications for formatting, checking syntax, and testing code; can support multiple languages.
• Library: Collection of pre-built resources (objects and functions) for use in programming.
• Interpreter: Directly executes high-level language instructions without translating them to machine language.
• Assembler: Converts low-level assembly instructions into machine language.
• Compiler: Converts high-level programming code into machine-readable code.

Algorithms, Pseudocode, and Flowcharts

• An algorithm is a set of steps leading to problem solutions, expressed in simple language.
• Example algorithm for calculating the volume of a rectangle involves steps to get dimensions, compute the volume, and display the result.
• Problem-solving steps in programming include:
  • Problem Analysis
  • Algorithm Design
  • Coding
  • Execution

Flowchart Creation Rules

• Use standard symbols only.
• Logic must flow top to bottom and/or left to right.
• Each symbol should have one entry and one exit point, except decision symbols.
• Operations in symbols should be independent of programming languages.
• Decision branches must be clearly labeled.