值类型

An entity is a value, object, subobject, base class subobject, array element, variable, function, instance of a function, enumerator, type, class member, template, or namespace.

实体是一个值，对象，子对象，基类子对象，数组元素，变量，函数，函数的实例，枚举符，类型，类成员，，名字空间。

On the other hand, floating types have density much smaller than 1, which means that there are real numbers unrepresented between consecutive floating values (i.e. there are gaps).

另一方面，点类型的密度远小1，味着在相邻的点值之间存在无法表示的实数(即有一定间隙)。