...language.
PROTÉGÉ-II uses MODEL (Gennari, 1993), which is an extension of CLIPS (NASA, 1991), as the ontology-definition language.

...behavior.
An earlier version of PROTÉGÉ-II allowed the developer to compile knowledge-acquisition tools to executable programs. However, the performance of a noncompiling run-time system is sufficient, and the major advantage of the latter approach is that it does not require a time-consuming compilation step.

...metatool.
Because certain bugs in DASH manifest themselves in window layouts (e.g., problems with the layout algorithm and custom tailoring of window layouts), certain rules belong to multiple rule sets.

Henrik Eriksson