GoDaddy Webmail Is The Way Of Sending & Receiving Emails From Web Browser Instead Of Using Email Provider Like Gmail, etc. All Email Servers Provides You A Storage Where Your Messages And Emails Are Saved. GoDaddy Webmail Allows You To Check Emails From Those Accounts Which Are Associated With Your Domain Name From GoDaddy. This lets you send and receive mail from anywhere in the world, from any device, as long as you have an internet-connected web browser. For This You Need To Purchase A Plan From GoDaddy To Relate It With Your Domain Name.
GoDaddy Mobile Apps Are Also Available For Both Android And iOS Devices To Establish A Secure Connection For Your GoDaddy Webmail. As It is Very Good But It Also Has Some Difficulties While Using.
Your Email Will Remain In Your Provider's Server So If You Don't Have Access To It Due To Any Way Like Provider's Server Is Down Or No Internet, You Will Not Be Able To Access Your Email With Using Webmail.
Office 365 Is A Huge Topic Which Might Discuss Soon, But Basics Will Be Here Now. Office 365 Allows You To Access Your Email Through Webmail. Hope This small Article Will Also Help You, If We Have made Some Mistake In This Post Or Something Is Missing Then Ask For It.