what is the importance of "namespace" in c# program?

Answer 1

Namespsaces are used to contain classes. Its basically like a bigger class used to contain a lot of different classes

Answer 2

namespace is used for this:

Console.WriteLine("Hello, World!);

instead of writing
System.Console.WriteLine("Hello, World!);

The namespace keyword is used to declare a scope. The ability to create scopes within your project helps organize code and lets you create globally-unique types.