The correct website to log into your Chase bank account is www.chase.com, and not www.chasebank.com. The latter site will just give you a 404 error. The former is the official website of Chase Bank, one of the major money-center banks in the US. It is one of the Big Four banks, with diverse divisions, including hedge fund operations, retail and institutional banking, card services, and more. It has also the third largest depositor base in the United States, behind Wells Fargo and Bank of America, and therefore has millions of customers.
On this site, you can access your Chase bank account online, check your bank statements, transfer money among your Chase accounts and to external accounts, and schedule bill payments. If you prefer to do your banking with a live person, you can also find out the nearest Chase bank branches, as well as the nearest ATM machines, on this website. So, for all your online banking needs, visit www.chase.com, not www.chasebank.com.