You don't actually need to log on, until you want to buy something.

However, if you are browsing from computer at home, there is no reason not to log in and never log out, as we run a fully secure site. That way, you have access to your account.

If browsing from a shared computer (eg internet cafe, or one at a friends house) you only need to log in when you want to take something to checkout for purchase. (You will be prompted to log in automatically). When finished shopping make sure to log out, and close the browser if on a shared computer.