The login form fields are already filled out with my information on a shared computer

Forms Autocomplete - This is a feature of the latest browsers which makes it easier to fill out online forms by remembering what was previously typed into the form’s text boxes, and automatically inserting this information where appropriate. The kind of information remembered includes previous text entries, usernames and passwords, and web addresses when typed into the browser’s address bar. In the case of a home computer where you are sure no unauthorised person will use your computer, these settings are safe and helpful. In the case of public or shared computers, this feature should ideally be disabled.