Thunderbird is a free email application that’s easy to set up and customize - and it’s loaded with great features. Ever dreamed of having a personalized email address (such as "email@example.com") for you, your family or your business? Thunderbird makes this easy - you can sign up for a new email address within Thunderbird, and it will all be set up automatically for you ready to send and receive. One-click Address Book is a quick and easy way to add people to your address book. Add people by simply clicking on the star icon in the message you receive. Two clicks and you can add more details like a photo, birthday, and other contact information.