Creating Your First Class

public class EventTicket {
    public String eventName;
    public Decimal price;

    public String describe() {
        return eventName + ' — R' + price;
    }
}

EventTicket ticket = new EventTicket();
ticket.eventName = 'Summer Music Festival';
ticket.price = 350;

System.debug(ticket.describe()); // "Summer Music Festival — R350"

1. public class EventTicket { — the blueprint.
2. public String eventName; — a field.
3. public Decimal price; — another field.
4. (blank line)
5. public String describe() { — a method living inside the class, alongside the fields.
6. return eventName + ' — R' + price; — eventName and price here refer to that specific object's values — the same method, called on a different EventTicket object, would use that object's own data instead.
7. } — closes describe().
8. } — closes the class.
9. (blank line)
10. EventTicket ticket = new EventTicket(); — creates an object.
11. ticket.eventName = 'Summer Music Festival'; — sets its name.
12. ticket.price = 350; — sets its price.
13. (blank line)
14. System.debug(ticket.describe()); — calls the method on this object, logging "Summer Music Festival — R350".

EventTicket vipTicket = new EventTicket();
vipTicket.eventName = 'Tech Conference';
vipTicket.price = 1200;

EventTicket generalTicket = new EventTicket();
generalTicket.eventName = 'Tech Conference';
generalTicket.price = 450;

System.debug(vipTicket.describe());     // "Tech Conference — R1200"
System.debug(generalTicket.describe()); // "Tech Conference — R450"

1. EventTicket vipTicket = new EventTicket(); — the first ticket.
2. vipTicket.eventName = 'Tech Conference'; — same event.
3. vipTicket.price = 1200; — a higher price.
4. (blank line)
5. EventTicket generalTicket = new EventTicket(); — a second, separate ticket.
6. generalTicket.eventName = 'Tech Conference'; — same event name.
7. generalTicket.price = 450; — a different, lower price.
8. (blank line)
9. System.debug(vipTicket.describe()); — logs "Tech Conference — R1200".
10. System.debug(generalTicket.describe()); — logs "Tech Conference — R450".

One describe() method, reused by every ticket object — each call naturally reflects that specific ticket's own price, because the method reads its own object's fields.