WaMu, short for Washington Mutual, was a savings bank and financial services company based in the United States. Founded in 1889, it grew to become one of the largest savings and loan associations in the country, offering a range of services including mortgages, savings accounts, and credit cards. In 2008, during the financial crisis, WaMu faced significant losses due to its exposure to subprime mortgages. The bank was seized by the Office of Thrift Supervision and its banking operations were sold to JPMorgan Chase, marking one of the largest bank failures in U.S. history.