Class in Java::

1. class:

• A class is a blueprint or template used to create objects.
• It defines the properties (variables) and behaviors (methods) that the objects created from it will have.

2.Use the class keyword:

• A class must be declared using the class keyword.

class MyClass {
}

3.Class name rules:

• The class name must start with a letter (A–Z or a–z).
• It cannot start with a digit.
• It must not contain spaces.
• Special characters are not allowed except _ and $.
• Java reserved keywords cannot be used as class names.

4.Naming convention:

• By Java convention, the class name should start with a capital letter, and if it contains multiple words, each word should start with a capital letter.

class StudentDetails

5.Curly braces are mandatory:

• The body of a class must be enclosed within curly braces { }.

class Car {
    // fields and methods
}

6.One public class per file:

• A .java file can contain only one public class.

7.File name rule:

• If a class is declared as public, the file name must be the same as the public class name.

public class Student {
}

8.Access modifiers:

• A class can have an access modifier like public or no modifier (default).
• Top-level classes cannot be private or protected.

9.main() method is required to run:

• To execute a Java program, the class must contain the main() method.

public static void main(String[] args) {
}

10.Multiple classes in one file:

• Multiple classes can be defined in a single file, but only one can be public.