The integer and real types represent the obvious. An integer object may have any integer value from -2147483648 to 2147483647. An object of the real type can represent values with up to 15 digits of precision. After discussing how to declare new types, the remaining built-in types can be described by specifying how they would be declared as new types.
The type and subtype definitions follow the rules: The access, file and incomplete type definitions are discussed in the next chapter. The other kinds of types are described in the following sub-sections.
Enumeration types
Real and Integer types
Physical types
Array types
Record types