Tasks can remember your log in information for you so you don't have to enter it every time. Check the 'Remember Me' checkbox on the Log In Screen and your username and an encrypted version of your password will be stored on your computer. The next time you try to access a page in Tasks you will be automatically logged in using the information stored in your cookies.
If you are using the 'Remember Me' feature, you should bookmark the page you want to start on in Tasks, not the Log In Screen.
You should only use this feature if you are working in an environment where other people are not using your computer or your login to your computer, or they will be able to access your Tasks data.
Clicking the Log Out Link will delete the cookies stored on your computer and you will need to log in again.