No.
If you do not sign-in before adding products to your card and clicking checkout you will be asked to enter an email address on the checkout screen.
If this is your first order an account will be automatically created. A username and password will be sent by email.
If you are a returning customer and you specify the same email address used on previous orders the current order will be associated with your account.
Please note that you will have to sign-in to see your order status or order history.