Introduction to Python Programming

Introduction to Programming Languages

• A program is a set of instructions that tells a computer how to perform a computation.
• Programming languages are used to write programs.
• Python is a popular programming language.

Python

• Created by Guido van Rossum at Centrum Wiskunde & Informatica (CWI) in the Netherlands.
• Released in 1991.

Features of Python

• Easy to learn.
• General-purpose, meaning it can be used for various tasks.
• High-level, meaning it's closer to human language than machine language.
• Platform independent, meaning it can run on different operating systems.
• Requires few lines of code for complex tasks.
• Simple syntax.
• Case-sensitive.
• Interpreted language, meaning it executes code line by line.
• Free to use and distribute.

Applications of Python

• Building websites.
• Programming robots.
• Developing artificial intelligence applications.
• Developing games.
• Performing scientific computations.

Installing Python

• Download from www.python.org/downloads.
• Double-click the .exe file and follow the installation instructions.

Getting Started with Python

• Interactive Mode: Default mode, launched by typing Python in the terminal. (or by clicking on Start > Scroll down to Python 3.7 > IDLE (Python 3.7)).
• Script Mode: Used for writing longer programs. Create and edit Python files (.py extension) using a text editor.

Components of IDLE Python

• Title Bar: Displays the name of the application and the document. Includes minimize, maximize/restore, and close buttons.
• Menu Bar: Contains menus with options for:
  • File: Opening, saving, closing files, exiting IDLE.
  • Edit: Cutting, copying, pasting, searching, and replacing text.
  • Shell: Working with the interactive mode.
  • Debug: Finding and fixing errors in code.
  • Options: Configuring IDLE settings.
  • Window: Managing open windows.
  • Help: Accessing Python documentation.
• Command Prompt: Denoted by '>>>'. It's where you type Python code.
• Status Bar: Indicates the current status of the cursor and provides helpful information.

Working in Interactive Mode

• Instructions are executed line by line.
• Commands are typed after the '>>>' prompt.
• Results or errors are shown immediately.
• Useful for testing small code snippets.

Printing a Message

• The print() function is used to display output on the screen.
• Example:

  >>> print("Hello World")
  

  This will print "Hello World" on the screen.

Note About Case Sensitivity

• Python is case-sensitive, meaning print (lower case) and Print (upper case) are different.