Do objects of classes necessarily reside in heap memory?

In C#, class objects are usually located on the heap, as classes are reference types. However, this is not always strictly necessary:

• If a class object is created using the new operator, it is placed on the heap.
• If a class object is a field of a struct (value type), it can reside on the stack or inside another struct.
• There are also compiler and runtime optimizations that can influence object placement.

Unlike classes, structs are value types that are typically stored on the stack or inline within other objects.