Essential .NET, Volume 1: The Common Language Runtime

Types at Runtime

Types by themselves are rarely all that useful. What makes types interesting is the ability they give programmers to have instances of types to interact with. An instance of a type is either an object or a value, depending on how the type is defined. Instances of the primitive types are values. Instances of most user-defined types are objects, although one can define types that yield values, as Chapter 5 will illustrate in great detail.

Every object and every value is an instance of exactly one type. The affiliation between an instance and a type is often implicit. For example, declaring a variable or field of type System.Int32 results in a block of memory whose affiliation with its type exists only by virtue of the executable ...