However they contain necessary data and methods to describe an aspect of reality. Basic data objects are for example JulianTime , Vector3D and Observer .
Tools controlling basic objects often bear the same name as the objects.
For example the basic object Vector3D is controlled by the tool Vector3D . The same holds for Observer , but not for JulianTime . The latter one is controlled by a tool called Calendar . Of particular interest is JulianTime because it serves as basic object for other time dependent objects. It allows for representing time in a linear manner counting days and seconds of days with a long term accuracy of about ten picoseconds.