# Instance

One object made from a class, with its own data.

## What is **Instance** in JavaScript?

**Instance** — One object made from a class, with its own data.

```javascript
class Book {
    constructor(title) {
        this.title = title;
    }
}

const guide = new Book("JavaScript");
```

Level: Journeyman · [More JavaScript terms at this level](https://www.ask-codey.com/glossary/subjects/javascript/journeyman)

Updated: September 27, 2026

## In other subjects

- [Instance in C#](https://www.ask-codey.com/glossary/instance-c-sharp)
- [Instance in Java](https://www.ask-codey.com/glossary/instance-java)
- [Instance in OOP](https://www.ask-codey.com/glossary/instance-oop)

Source: https://www.ask-codey.com/glossary/instance-javascript