When paying by credit card, PayPal processes the credit card payment and will verify that your Internet browser is running Secure Sockets Layer 3.0(SSL) or higher. The information is protected by SSL with an encryption key length of 128 bits (the highest level commercially available). For more information on how PayPal protects your information, visit PayPal to find out more about security of your credit card information.
If you are concerned about the security of payment via bank transfer you should check this with your own bank which you have internet banking with as we do not collect any of your bank account information from you.
Shern.com will never email you to ask for your credit card or bank account passwords.