What is namespace in Typescript? How to declare a namespace in Typescript?

Internal Modules are known as namespaces in Typescript.Namespaces are used to maintain the legacy code of typescript interally. A namespace is simply a way to logically group related classes or interfaces in a wrapper.
Synatax for creating namespace in Typescript

namespace YourNameSpace { 
   export class Class1 {  }  
   export class Class2 {  }  
}