Calendar App shows a Microsoft and Hotmail account. Why are they - Microsoft Community

use microsoft phone , use outlook email account phone. when creating new event on calendar, can pick between microsoft account , hotmail account. don't understand why 2 separate things. also, microsoft account doesn't sync between laptop , phone. i'm confused why it's called hotmail account when have outlook email address. how close "hotmail" account or merge microsoft (outlook) account?

Outlook.com / My Account and information / Other