Q. Some Buddhist rock-cut caves are called chaityas while the others viharas. What is the difference between the two?
Answer: Chaitya is a place of worship while vihara is the dwelling place of the monks
Notes: The Buddhist architecture is mainly consisting of Chaityas, Viahras, Stupa and Stambhas.  There are mainly two types of distinct architecture related to the caves, i.e. Chaitya and Viharas. Chaityas were the place of worship in Buddhism, whereas Viharas were dwelling place of monks