#32 – Built-In Types

The C# language includes a variety of built-in types that you can use in your C# program.  Each has a built-in C# keyword for the type, but maps to a type in the .NET Framework.  The C# keyword is just shorthand for the complete type name as it exists in the framework.

Here are all of the C# built-in types that are value types, along with their class name in the .NET Framework.

• bool – System.Boolean – 1 byte  (true|false)
• byte - System.Byte – 1 byte   (0 to 255)
• sbyte - System.SByte – 1 byte  (-128 to 127)
• short - System.Int16 – 2 bytes  (-32,768 to 32,767)
• ushort - System.UInt16 – 2 bytes  (0 to 65,535)
• int - System.Int32 – 4 bytes  (-2,147,483,648 to 2,147,483,647)
• uint - System.UInt32 – 4 bytes  (0 to 4,294,967,295)
• long - System.Int64 – 8 bytes  (-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807)
• ulong - System.UInt64 – 8 bytes  (0 to 18,446,744,073,709,551,615)
• float - System.Single – 4 bytes  (±1.5e−45 to ±3.4e38, 7 digit precision)
• double - System.Double – 8 bytes  (±5.0e−324 to ±1.7e308, 15-16 digit precision)
• decimal - System.Decimal – 16 bytes  (±1.0 × 10−²⁸ to ±7.9 × 10²⁸, 28-29 digit precision)
• char - System.Char – 2 bytes  (U+0000 to U+ffff, UTF16 Unicode character)