There is the organization membership which is the yearly $100 membership for the organization, and there is the conference registration which costs $750. If you sign up for the user account, you get a $10 discount on the conference registration bringing it down to $740, and if you sign up for the organization membership, you will get a member ID/discount code that may be used by everyone within your organization. This $50 discount will bring your conference registration cost down to $690 (as you will need to sign up for the user account in order to apply the membership discount).