Space is one of the few fundamental magnitudes in physics. This means that space can not be defined through other quantities because there are no fundamentalists known. Therefore, space, as is the definition of other fundamental factors such as time and mass, is determined by measurement.
The default space interval is the meter, since 1983 defined as the distance that takes light in 1 / 299,792,458 seconds in vacuum. This definition, which is linked to the current definition of time, makes our place-time space a Minkowski space and justifies the special relativity theory by definition.
In classical physics, space is conceived as a three-dimensional Euclidean space in which each position can be described by three coordinates. Relativistic physics is more concerned with space time, which is modeled as a four-dimensional topological space. Also see
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