Python:

What is Python?

Python is a high-level, interpreted, general-purpose programming language known for its simplicity, readability, and versatility. It is widely used in web development, data science, machine learning, automation, and more.

✅ Key Features of Python:
✔ Easy to Learn – Simple syntax similar to English.
✔ Cross-Platform – Works on Windows, macOS, and Linux.
✔ Extensive Libraries – Pre-built modules for various applications.
✔ Object-Oriented & Functional – Supports multiple programming paradigms.
✔ Scalable & Efficient – Used by companies like Google, Netflix, and Instagram.

Why Use Python?

📌 Beginner-Friendly – Ideal for new programmers.
📌 Versatile – Used in multiple industries (AI, web dev, cybersecurity).
📌 Large Community – Active support and regular updates.
📌 Automation – Easily automates repetitive tasks.
📌 Data Science & AI – Powers advanced analytics and machine learning.

Python Installation & Setup

🔹 Download Python: Official Website
🔹 Install on Windows/macOS/Linux
🔹 Check Installation:

python --version

🔹 Use Python Interactive Mode:

python

🔹 Exit Python Shell:

exit()

Python Syntax & Basics

1️⃣ Variables & Data Types

name = "John"  # String
age = 25       # Integer
price = 99.99  # Float
is_active = True  # Boolean

2️⃣ User Input

name = input("Enter your name: ")
print("Hello, " + name)

3️⃣ Operators

a = 10
b = 5
sum = a + b   # Addition
diff = a - b  # Subtraction
prod = a * b  # Multiplication
quot = a / b  # Division

Control Structures

1️⃣ Conditional Statements (if-else)

age = 18
if age >= 18:
    print("You are an adult")
else:
    print("You are a minor")

2️⃣ Loops (for, while)

# For Loop
for i in range(5):
    print("Iteration:", i)

# While Loop
x = 1
while x <= 5:
    print(x)
    x += 1

Functions & Modules

1️⃣ Defining Functions

def greet(name):
    return "Hello, " + name

print(greet("Alice"))

2️⃣ Importing Modules

import math
print(math.sqrt(16))  # Output: 4.0

3️⃣ Custom Modules

# mymodule.py
def welcome():
    return "Welcome to Python!"

# Import in another script
import mymodule
print(mymodule.welcome())

Python Data Structures

1️⃣ Lists (Dynamic Arrays)

fruits = ["apple", "banana", "cherry"]
fruits.append("orange")  # Add item
print(fruits[1])  # Access item

2️⃣ Tuples (Immutable Lists)

colors = ("red", "green", "blue")
print(colors[0])  # Output: red

3️⃣ Dictionaries (Key-Value Pairs)

person = {"name": "John", "age": 30}
print(person["name"])  # Output: John

4️⃣ Sets (Unique Elements)

numbers = {1, 2, 3, 4, 5}
numbers.add(6)
print(numbers)

Object-Oriented Programming (OOP) in Python

1️⃣ Creating a Class & Object

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def greet(self):
        return f"Hello, my name is {self.name}"

p = Person("Alice", 25)
print(p.greet())

Python File Handling

1️⃣ Reading a File

with open("example.txt", "r") as file:
    content = file.read()
    print(content)

2️⃣ Writing to a File

with open("example.txt", "w") as file:
    file.write("Hello, Python!")

Python Libraries & Frameworks

📌 Web Development – Flask, Django
📌 Data Science & AI – NumPy, Pandas, Matplotlib, TensorFlow
📌 Automation – Selenium, BeautifulSoup
📌 Game Development – Pygame
📌 Cybersecurity – Scapy

Python for Data Science

🔹 1️⃣ Using Pandas for Data Analysis

import pandas as pd
df = pd.read_csv("data.csv")
print(df.head())  # Display first 5 rows

🔹 2️⃣ Using Matplotlib for Data Visualization

import matplotlib.pyplot as plt
x = [1, 2, 3, 4]
y = [10, 20, 25, 30]
plt.plot(x, y)
plt.show()

🔹 3️⃣ Using NumPy for Numerical Computation

import numpy as np
arr = np.array([1, 2, 3, 4, 5])
print(np.mean(arr))  # Calculate mean

Python for Machine Learning

🔹 1️⃣ Using Scikit-learn for ML Models

from sklearn.linear_model import LinearRegression
model = LinearRegression()

🔹 2️⃣ Using TensorFlow for Deep Learning

import tensorflow as tf
print(tf.__version__)  # Check TensorFlow version

Python for Automation (Scripting & Web Scraping)

1️⃣ Automating Tasks with Python

import os
os.system("mkdir new_folder")  # Creates a folder

2️⃣ Web Scraping with BeautifulSoup

import requests
from bs4 import BeautifulSoup

url = "https://example.com"
page = requests.get(url)
soup = BeautifulSoup(page.content, "html.parser")
print(soup.title.text)

Python Career Opportunities & Salary

📌 Job Roles:
✔ Python Developer
✔ Data Scientist
✔ Machine Learning Engineer
✔ Software Engineer
✔ Automation Engineer

Python Trends & Future

🚀 1. AI & Machine Learning – Python is leading AI innovations.
🚀 2. Automation & Robotics – Automating repetitive tasks.
🚀 3. Web & App Development – Flask & Django for scalable applications.
🚀 4. Cloud Computing – AWS, Azure, Google Cloud use Python.
🚀 5. Cybersecurity – Ethical hacking, security automation.

Conclusion

✅ Python is one of the most powerful and versatile programming languages today.
✅ It is used in various fields including web development, AI, data science, and automation.
✅ With its simple syntax and vast libraries, Python is ideal for beginners and professionals alike.

🚀 Ready to learn Python? Start coding today!