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.
Yahoo! Mail
When asked about these changes, Yahoo! explained that the changed words were common terms used in web scripting, and were blacklisted to prevent hackers from sending damaging commands via the program's HTML function. Starting before February 7, 2006, Yahoo! Mail ended the practice, and began to add an underscore as a prefix to certain suspicious words and word fragments.