Cookies Required

You must have session cookies enabled in your web browser before you can add items to your shopping cart. These cookies are not written to your computer's hard drive. They allow your selections to be saved while you shop, and are then deleted when you close your browser or log out of your registered user session.

Web Browsers

This site is designed to work with Microsoft Internet Explorer 6.0 or later and Mozilla Firefox 1.0 or later. Other types of web browsers may work, but some pages may not display correctly in all cases.

Tips for Registered Users

If you are a registered user, your profile information is stored securely for your use in future visits. Use the "My Account" page to keep your information up to date:

Current Address:

Keep your current address and your contact phone numbers up to date.

E-mail and Password:

If your e-mail address changes, be sure to update it so you will receive your order and shipping confirmations. Also, change your password regularly for increased security.

Payment Methods:

If available, you can securely save new payment methods or update existing ones -- for instance, update your credit card expiration date.

Order Tracking & History:

Check the current status of your orders and view past orders.

My Memberships:

Authenticate yourself as a member of a special group. This may allow you to view and purchase products or services available only to members of that group.

Shipping Addresses:

Edit and manage your saved shipping addresses. For instance, you might save your grandma's address under the nickname "Grandma". Then during checkout, you'll be able to select from your list of shipping addresses. Data fields will automatically be filled in for you.

Sciences and Mathematics