At a simple level, Profiles lets you specify your work account and personal account(s) separately, and you can switch between them quickly. Look under Settings or go straight to edge://settings/profiles in the browser if you already have it.
For anyone who’s ever had to sign into a work-related website but using their Microsoft Account (eg Outlook.com / Hotmail / MSN / Zune etc credentials), this can be handy as you do it without resorting to an InPrivate tab.
Once you’ve set up profiles, you can individually enable Sync, Password retention etc, for each, though you will see that only some of the options are lit up in the current version of the Beta. More to come soon – ahead of the expected January 15th release. Probably.
To change profiles, just click on the associated picture on the browser toolbar and if you like, you can even pin the individual profiles to your taskbar so you can quickly jump into each one, rather than having to launch the browser and do the switcheroo.
You may want to import and export favourites between profiles – like Chrome, Edge no longer stores these as shortcut files that can be simply moved around, instead holding the favourites to a “bookmarks” file.
If you want to see where Edge Beta is saving your profile info, go to edge://version in the browser and check out the Profile Path. Mind how you go if you decide to start editing stuff directly.
To read more about profiles and the new Edge, see here.