2. Syntax and Basics of the Language #
Python stands out for its simple and readable syntax. In this section, we will cover the fundamentals of writing Python code.
1. Indentation: A Mandatory Rule #
Unlike other languages that use curly braces {} or keywords (begin / end), Python uses indentation to structure code.
❌ Bad Example (Indentation Error) #
if 5 > 2 :
print("Five is greater than 2") # Error: Missing indentation!
✅ Correct Example #
if 5 > 2:
print("Five is greater than 2") # Correct indentation
📌 Rule: Indentation is usually 4 spaces per level (avoid mixed tabs).
2. Variables and Data Types #
A variable is a memory location where a value is stored. Python is dynamically typed, meaning it automatically detects variable types.
📌 Declaration and Assignment #
name = "Alice" # String
age = 25 # Integer
pi = 3.14 # Float
is_active = True # Boolean
📌 Main Data Types in Python #
| Type | Example | Description |
|---|---|---|
str (string) |
"Hello" |
Text |
int (integer) |
42 |
Whole number |
float (floating point) |
3.14 |
Decimal number |
bool (boolean) |
True, False |
True or False |
list (list) |
[1, 2, 3] |
Mutable collection |
tuple (tuple) |
(1, 2, 3) |
Immutable collection |
dict (dictionary) |
{"name": "Alice", "age": 25} |
Key-Value pair |
set (set) |
{"apple", "banana"} |
Unique values set |
3. Output and Comments #
📌 The print() Function
#
It allows displaying text or variables on the screen.
print("Hello, world!")
name = "Alice"
print("Hello", name)
👉 Output:
Hello, world!
Hello Alice
📌 Comments #
Comments help explain the code without being executed.
✅ Single-line comment
# This is a comment
print("Hello") # Displaying a message
✅ Multi-line comment
"""
This is a comment
spanning multiple lines.
"""
print("Python is awesome!")
📌 Summary:
✔️ Python uses indentation to structure code.
✔️ Variables are dynamic and can store different data types.
✔️ The print() function allows displaying text.
✔️ Comments help document code.
💡 Ready for the next step? Let’s dive into operations and expressions in section 3! 🚀