You can now return values by reference from a method as well as consume them. This is a little like working with pointers in C but safer. For example, you can only return references that were passed to the method, and you can't modify references to point to a different location in memory. This is a very specialist feature, but in certain niche situations, it can dramatically improve performance.
Consider the following method:
private static ref string GetFirstRef(ref string[] texts){ if (texts?.Length > 0) { return ref texts[0]; } throw new ArgumentOutOfRangeException();}
You could call this method like so, and the second console output line would appear differently (one instead of 1):
var strings = new string[] { "1", "2" };
