Python Membership Operators

1. What are Membership Operators?

Membership operators are used to check whether a value is present in a group.

In simple words:
👉 They check “Is this item inside that group?”

Python has two membership operators:

• in

• not in

2. The in Operator

in returns True if the value exists in the group.

Example with String

Output:

Example with List

Example with Tuple

3. The not in Operator

not in returns True if the value does NOT exist in the group.

Example

Output:

4. Membership Operators with if Statement

Example

Another Example

5. Membership Operators with User Input

Example

6. Membership in Dictionary (Keys Only)

Membership operators check keys, not values.

Example

Output:

7. Common Beginner Mistakes

❌ Checking Value Instead of Key

✔ Correct:

❌ Wrong Case in String

Output:

Strings are case-sensitive.

8. Simple Practice Examples

Example 1: Check Letter

Example 2: Check Number in List

Example 3: Email Check

9. Summary (Membership Operators)

✔ Used to check presence
✔ in means exists
✔ not in means not exists
✔ Works with string, list, tuple, dictionary
✔ Very useful in conditions

📘 Perfect for Beginner eBook

This chapter is ideal for:

• Python beginner books

• School & college students

• Self-learners

If you want next, I can write:

• Bitwise Operators

• Operator Exercises

• if–else statements

• Loops (for, while)

• MCQs with answers

Just tell me 😊