What is a feature - today?

The variety of definitions of features has an impact on the comparability and interoperability of data sets, particularly when they are evaluated digitally. The following considerations are based on an analysis of excavation guidelines from various European regions and informal field archaeology practices. The results reveal significant discrepancies in the assignment of numbers to features and the recording of data types. A formula is introduced that can capture the structure of feature descriptions from heterogeneous documentation systems, thereby enabling improved data interoperability.