From Xojo Documentation
A Double is an intrinsic data type in REALbasic. A Double is a number that can contain a decimal value, i.e., a real number. It can take on a value between 2.2250738585072013 e-308 and 1.7976931348623157 e+308. In other languages, REALbasic's Double may be referred to as a double precision real number. Because Doubles are numbers, you can perform mathematical calculations on them. Doubles use 8 bytes of memory. The default value of a Double is 0.0.
The VarType function returns a value of 5 when passed a Double.
The Double data type allows you to store and manage floating point numbers.
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