Types Aliases and Interface are tricky..

type BirdType = {
  wings: 2;
};

interface BirdInterface {
  wings: 2;
}

• Both declare the shape of an object
• Both support extending other interfaces and types
• It's possible to intermix their use
• Interfaces are open whereas type aliases are closed
• Typescript gives better error messages for interfaces
• Prefer interfaces for publicly exposed types

Sources:

• TS Playground

• Interfaces vs Types

• Interfaces vs Type Aliases: what's the difference?

• TypeScript: Should you use Types or Interfaces?