what is {0} this.

Question

why not {1}

Answer 1

Both works.

Console.Write("I am {0}, and my age is {1}, {2}", name, age, greeting);

// The {x} is a place holder for a variable. It's just another way instead of using "I am + name + ", and my...

Answer 2

It's a place holder in the string. For example:

string b = "world."; Console.WriteLine("Hello {0}", b);

Would produce this output:

Hello world.