If you are using a stand-alone desktop e-mail program like Mozilla Thunderbird, Mailbird, or an older program like Eudora or Microsoft Outlook (the second is not recommended), and you click on a mail link like this one, then the program should start running and let you send a message, filling in my address and the subject line.
If you click on the link above and it doesn't do this, you don't have a stand-alone program. You are most likely using a Web-based mail interface like Gmail, Hotmail, Yahoo, etc. Instead, click on the button below, then open up your mail program, create a new message and paste this address into the "To:" field
using Ctrl-V. Fill in the subject line, type your message and then send it.
When you are finished, click the back button in your browser to return to the previous screen.