The discovery, study and application of multiple-bubble acoustic cavitation since the 20′s of the last century are first briefly reviewed. Attention then is drawn to the realization of a stable single bubble in the early 1990′s, after which experimental and theoretical studies of acoustic cavitation progressed rapidly, including studies of the extreme conditions(high temperature, high pressure and high density) inside a cavitation bubble and the mechanism of its sonoluminescence. The much earlier observation of a transient single bubble in China in the 1960′s is next described together with some recent results. Finally, a most recent(March 2002) experiment by Taleyarkhan R P et al. on nuclear emission by acoustic cavitation which has stirred wide attention is recounted.