What is Authenticated checkout?

The Authenticated check out is a feature best suited for such events where the Member authentication is required before Members are allowed to proceed to buy ticket. This mean, rather than asking the Members to enter the email ID and do the validation, the Members are asked to enter the Membership email ID and Password and once authenticated, the system would let him/her proceed further. 

The major difference here is that it is members only event. Second, if the validation fails, the error message is shown and no tickets are displayed. 

Also, the option to join the chapter is also provided on the first section of the checkout page.
Please refer to the attached Screenshot.