Use record types in C# 9 A record type in C# 9 is a lightweight, immutable data type (or a lightweight class) that has read-only properties only.

Developers should have a basic proficiency of a language's data types. In this article, Irina Medvinskaya presents an overview of two types of predefined C# variables: value types and reference types.

The C# language provides support for two types of data: value types and reference types. While a variable of type System.String is a reference type, a variable of type Int32 is a value type.