Interactive programs let the users enter choices and invoke the corresponding routines.

Classical Kleinian groups are discrete subgroups of Möbius transformations which act on the Riemann sphere with a nonempty region of discontinuity.

Cheeta swings from vine to vine through le tout Hollywood, from saucy poolside romps with Marlene Dietrich, Mercedes de Acosta, Clark Gable and Clara Bow, to suave yachtboard revels — “a couple of cocktails, some caviar and a good cigar” — with Katharine Hepburn, Humphrey Bogart, and Errol Flynn.

The stadion was used specifically for human athletic contests whereas the Greek hippodrome and later the Roman circus were used for equestrian events. The gymnasion and the palaistra were used for training purposes for human athletic events.