1. Highly Recommend / Forced to use created microsoft account
But you can create a local account but the windows 10 makes it hard for you to use the OS you need to login to everything then

2. New Browser called Edge

3. Start Menu is Back!
Its a mix of windows 8 metro & windows 7 start menu

4. Cordova you can interac & talk to her like siri

5.Cool dynamic info graphic that updates as your files copy feature

6. New look to the taskbar Calendar when you click on the date

7. The newly designed Mail,calendar,photos apps have a new look gone is Outlook express as all these apps built into      the OS