RocketMail was one of the first major, free webmail services. The service was originally aproduct of Four11 Corporation. For a brief time, RocketMail battled with Hotmail for the number-onespot among free webmail services. Four11, including RocketMail, was acquired by Yahoo! in 1997 for 92 million. Yahoo! assimilated the RocketMail engine. Yahoo! Mail was essentially the old RocketMailWebmail system.At the time of the transition, RocketMail users could either choose a Yahoo! ID, since they were not guaranteed the availability of their RocketMail ID on Yahoo!, or could use username.rmas their Yahoo! ID. Thus, they were able to keep their rocketmail.com address and receive the sameservices as all Yahoo! users. On 19 June 2008, Yahoo started the RocketMail brand again by allowingnew users to sign up for accounts under the rocketmail.com domain, which had not been possible sinceits acquisition of Four11 Corporation.In April, 2013, Yahoo closed support for creating new Rocketmailemail addresses, new users must use @yahoo.com, existing Rocketmail accounts are not affected.