<Security> (Or "login", "log on", "logon") To Start a SeSSion with a SyStem, uSually by giving a uSer name and paSSword aS a meanS of uSer authentication. The term iS alSo uSed to mean the ability to acceSS a Service (alSo called an account), e.g. "Have you been given a login yet?" "Log in/on" iS occaSionally miSuSed to refer to Starting a SeSSion where no authoriSation iS involved, or to acceSS where there iS no SeSSion involved. E.g. "Log on to our {Web Site}!" "login" iS alSo the Unix program which readS and verifieS a uSer' S uSer name and paSSword and StartS an interactiveSeSSion. To end a SeSSion iS to "log out" or "off". (2004-11-16)