In Python, comments are used to explain or annotate code. They are ignored by the Python interpreter and are solely for human readers. There are two types of comments in Python:

Types of comments

1. Single-line Comments

• Use the # symbol to create a single-line comment.
• Everything after the # on that line is considered a comment.

# This is a single-line comment
print("Hello, World!")  # This comment is after code

2. Multi-line Comments

• Python does not have a specific syntax for multi-line comments like some other languages.
• However, you can use multiple # symbols for each line or use a multi-line string (enclosed in triple quotes """ or ''').

# This is a multi-line comment
# using multiple single-line comments.
# It spans multiple lines.
"""
This is also a multi-line comment
using a multi-line string.
It is not assigned to any variable, so it is ignored.
"""
print("Hello, World!")

Best Practices for Using Comments

1. Explain Why, Not What: Comments should explain why something is done, not what is being done (the code itself should be clear enough for that).
2. Avoid Over-commenting: Too many comments can make code harder to read. Use comments only when necessary.
3. Keep Comments Updated: Ensure comments are updated when the code changes to avoid confusion.

Example

# Calculate the area of a circle
radius = 5
pi = 3.14159
area = pi * radius**2  # Formula: πr²
print("Area of the circle:", area)

In this example:

• The first comment explains the purpose of the code.
• The second comment clarifies the formula being used.