Yahoo! Mail
Yahoo! Mail is an email service launched in 1997 through the American parent company Yahoo!. Yahoo Mail provides four different email plans: three for personal use (Basic, Plus, and Ad Free) and another for businesses. By December 2011, Yahoo! Mail had 281 million users, making it the third largest web-based email service in the world. Since 2015 its webmail client also supports managing non-Yahoo e-mail accounts.
YPOPs!
YPOPs! (previously known as YahooPOPs!) is open-source software that provides POP3 and SMTP access to Yahoo! Mail. It is available on the Microsoft Windows, Linux, Solaris and Mac platforms. The software was released in 2006 with the latest update being from 2009.