This paper focuses on the concept of Digital Twins and the characterization of Digital Twins in terms of the spatio-temporal extent of the information based on which they operate. Following an in-depth literature review, we observe that even when Digital Twins (and variations of this concept) are qualified in terms of ‘levels of information integration’, strictly quantifiable metrics are rarely applied. To fill this gap, we propose the term ‘information basis’, which highlights the quantifiable extent of events occurring in space and time which have an influence on the functionality of the Digital Twin. Following a discussion on the implications of this term, we present an example Digital Twin and discuss how its different alternative implementations would fall on different points of the newly introduced information basis spectrum.