The problem of global and local tsunamis is discussed. The results of the observations of two global tsunamis in the Indian Ocean (1883 Krakatau volcano eruption and 2004 Sumatra earthquake) are summarized and compared. The directivity of both tsunamis is discussed. It is shown that the far field characteristics of both tsunamis are similar. In many cases the impact of local tsunamis can be significant. Such events can also occur in inland water: rivers, lakes, and artificial water supply reservoirs. The data of Russian tsunami events are collected and discussed. The collected material confirms the risk of tsunami and phenomena similar to tsunami in all water reservoirs and the necessity of informing the population about this hazard. Modeling of selected events is performed and discussed.