first and most important, is you can keep a copy of all your email, on your own computer both sent and recurved. You can store on a backup drive. Second you can

first and most important, is you can keep a copy of all your email, on your own computer both sent and recurved. You can store on a backup drive. Second you can use it as a collections centre for all your other emails, for example, your account at Microsoft, and or Google, and or Yahoo, etc. By having a copy on your own device you can delete old emails from the host that your provide. Saves room, and is less secure.