What does ‘declare module’ syntax accomplish in a .d.ts file?

Question

TypeScript Professional — Medium

What does ‘declare module’ syntax accomplish in a .d.ts file?

Accepted Answer

The 'declare module' syntax in a .d.ts file augments an existing module's type declarations by merging additional types into it from a separate file. This allows for extending the types of an already defined module without altering the original module's source code.