Namespaces (Packages)

Analogy: folder

Namespaces are like Folders on your Computer:

You can have a file named Resume.docx in your "Work" folder AND in your "Personal" folder. They don't conflict because they are in different Namespaces.

Without folders, you'd have to name them Work_Resume.docx and Personal_Resume.docx. Messy!

Why use Packages?

Avoid Naming Conflicts: Two libraries can both have a User class if they are in different packages.
Organization: Group related classes together (e.g., java.util for utilities, java.io for input/output).
Access Control: protected members are only visible to classes in the same package.

The Code

Java (Packages)

// File: src/com/myapp/users/User.java
package com.myapp.users;

public class User {
    // ...
}

// File: src/com/myapp/Main.java
package com.myapp;

import com.myapp.users.User; // Import to use

class Main {
    User u = new User();
}

C# (Namespaces)

namespace MyApp.Users {
    public class User {
        // ...
    }
}

Python (Modules)

Every file is a module.

# File: users.py
class User:
    pass

# File: main.py
from users import User
u = User()