Basic Python Syntax

1. Comments:

In Python, comments are used to annotate code and are preceded by the # symbol. Comments are ignored by the Python interpreter and are useful for providing explanations or context within your code.

# This is a single-line comment

"""
This is a
multi-line
comment
"""

2. Variables and Data Types:

Python is dynamically typed, meaning you don’t need to declare the data type of a variable explicitly.

# Variable assignment
name = "John"
age = 25
height = 5.9
is_student = True

Common data types in Python include:

• int for integers
• float for floating-point numbers
• str for strings
• bool for boolean values

3. Print Statement:

The print() function is used to display output. You can print variables, strings, or a combination of both.

print("Hello, Python!")
print("My name is", name)
print("I am", age, "years old.")

4. Indentation:

Indentation is crucial in Python for indicating blocks of code. Use consistent indentation (usually four spaces) to define the scope of loops, conditionals, and functions.

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

5. Conditionals:

Python uses if, elif, and else for conditional statements.

if score >= 90:
    grade = 'A'
elif score >= 80:
    grade = 'B'
else:
    grade = 'C'

6. Loops:

Python supports for and while loops.

# For loop
for i in range(5):
    print(i)

# While loop
counter = 0
while counter < 5:
    print(counter)
    counter += 1

7. Lists:

Lists are ordered, mutable collections in Python.

fruits = ["apple", "banana", "orange"]
numbers = [1, 2, 3, 4, 5]

8. Tuples:

Tuples are ordered, immutable collections.

coordinates = (3, 4)
colors = ("red", "green", "blue")

9. Dictionaries:

Dictionaries are key-value pairs.

person = {
    "name": "Alice",
    "age": 30,
    "is_student": False
}

10. Functions:

Functions are defined using the def keyword.

def greet(name):
    print("Hello, " + name + "!")

# Function call
greet("Alice")

11. Input from Users:

Use the input() function to get user input.

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

12. String Manipulation:

Python provides powerful string manipulation methods.

message = "Python is fun!"
length = len(message)
uppercase_message = message.upper()

13. Math Operations:

Perform basic math operations using +, -, *, /, and %.

result = 5 + 3
remainder = 10 % 3

14. Importing Modules:

Python’s functionality can be extended by importing modules.

import math

square_root = math.sqrt(25)

15. Whitespace Sensitivity:

Be mindful of whitespace as it is part of Python syntax.

# Good
if x > 0:
    print("Positive")

# Bad
if x > 0:
print("Positive")

Mastering these basic Python syntax elements will lay a strong foundation for your programming journey. In the upcoming sections, we’ll explore more advanced concepts and practical applications.