If you own an iOS device (iPhone, iPod or iPad) or Mac, then it is most likely that you own a iCloud email address. This email address is created when you first sign-in to iCloud with your Apple ID.
Your iCloud email account can easily be accessed when you are on a Mac or an iOS device, but that's another story for Windows PC users. This procedure explains how configure an iCloud email account to the Mail app of Windows 8.1:
Open Mail app, press the Windows key + C to open the Charms bar. Click on Accounts > Add an account > Others and select IMAP:
Enter your iCloud email address (firstname.lastname@example.org, email@example.com,...) and password. Click on Connect and fill in the following information: