What is the difference between interface and type in TypeScript?

Can you explain the difference between interface and type in TypeScript?

Sure! In TypeScript, both interface and type can be used to define the shape of an object, but they have some differences.

What are the key differences between them?

1. Extensibility: Interfaces can be extended using extends, while types can use intersections.
2. Declaration Merging: Interfaces support declaration merging, meaning you can define the same interface multiple times and TypeScript will merge them.

Can you give an example of when to use each?

Use interface when you want to define a contract for classes or when you need declaration merging. Use type for more complex types like unions or when you want to create a type alias.

Are there any performance differences between using interface and type?

Generally, there are no significant performance differences in terms of runtime. The choice between them is more about design and use cases.