Ymail.com is an alternate ending or domain for a Yahoo email address. Yahoo introduced the Ymail.com email address option in June 2008. The "Ymail" name stands for Yahoo Mail.
Yahoo Mail users can sign in to send and receive email at Ymail.com just as they would from the standard link for checking Yahoo mail online. The alternate domain “@ymail.com” can also be used as a substitute for “@yahoo.com” in a user’s e-mail address itself. Emails sent to “@ymail.com” will appear in the same inbox as e-mails sent to “@ymail.com.”
Yahoo Mail was launched by Yahoo! in 1997, and is the third-largest email service.