deriv LSK ETT STT aSTA ALPH OLDHOMEPAGE NEWHOMEPAGE
The epics or /itihAsa are the /mahAbhArata and the /rAmAyaNa. See wikipedia for blablabla.
The style of language in the epics is clearly later than the language of the vedas and clearly earlier than what can be called "classical Sanskrit" or "medieval Sanskrit". It mostly follows /pANini rules, but sometimes it doesn't.