The login information of the account's primary systems adminstrator starting with the text "user:", then the username, then the text "pass:" and then the password.
To the right of that is the command text, "Login As". Clicking on that allows you to log into the designated tool of the designated account as the primary sysadmin. This allows you to see what he sees, to diagnose problems, to give tutorials looking at the client's real data, and such functions pretending to be the primary sysadmin. Note that the effect on your cookies may cause you to have to login again as yourself to go back to using Webteam tools under your regular username.