What does this expression a[b] represent in C#

Question

I have often seen this expression in a maintenance code

Global["Name"]

What does this represent? I have used Global.Name but never Global["Name"]?

Is there are a place where this type of expression is used?

Answer 1

This is called an indexer. In that case, Global is probably some kind of dictionary or hashtable. "Name" is a key to access a particular item in that dictionary