C#: What is the difference between struct and class?

Struct — value type. Class — reference type.

Struct:

• Stack allocated.
• Copy by value.
• No inheritance.

Class:

• Heap allocated.
• Reference.
• Inheritance.

1// Struct
2public struct Point
3{
4    public double X { get; init; }
5    public double Y { get; init; }
6}
7
8// Class
9public class Person
10{
11    public string Name { get; set; }
12}

Key: Struct for small, immutable; class for complex objects.