Apa bedhe antara klase lan objek?

Question

Accepted Answer

A **klase** iku *cetak biru* utawa template sing nggolongake struktur (fields) lan tingkah laku (methods). A **objek** (utawa *instans*) iku bab konkreto sing dibangun saka cetak biru kuwi, nganggo nilai dewe-dewe ing memori.

## Cetak biru vs. instans

```text
class Car          ← ONE definition (the blueprint)
   │  fields: color, speed
   │  methods: accelerate()
   ▼
new Car("red")     ← many OBJECTS (instances), each with its own state
new Car("blue")
```

## Ing kode

```python
class Car:
    def __init__(self, color):
        self.color = color      # per-instance state
        self.speed = 0
    def accelerate(self):
        self.speed += 10

a = Car("red")                  # object #1
b = Car("blue")                 # object #2 — independent state
a.accelerate()
print(a.speed, b.speed)         # 10 0  → separate instances
print(a.color is b.color)       # False → different objects
```

Klase iku ana samubarang; sampeyan bisa nggawe akeh objek saka klase kuwi, saben siji nyimpen data saya mandiri.

## Kampang umum

- Klase dhewe ora nganggo memori per-instans nganti sampeyan nyitak.
- "Variabel klase" (padha antaraning instans) kalih "variabel instans" (per objek) — nyampur ngakibatake bug negara padha.

## Apa gunane

Iki pembedane paling dhasar ing OOP: konsep liyane kabeh ana ing pangrungu yen siji klase nyiptake akeh objek mandiri.

Kesalahaan ngakibatake negara padha ora diduga — kayata default mutable utawa list tingkat klase sing saben instans ora diduga padha.