Deleted Users Confusion/Worry

I'm not very tech smart but I just opened my finder to look through my computer and on the left side bar, favourites/devices area. I found a 'Deleted Users' file which i've never seen before. I'm confused how they got here and why I never saw it before.

It has two .dmg and one is 'aspnet.dmg' I don't know what that even is?

The other seems to be my older personal user account, lets just say its called 'M.dmg' which I again don't know how it got there. I did transfer my old computer on to this but i don't remember deleting it on my mac or anything about it ending up in this Deleted Users folder.

The user I use on my mac is the first one I made, the user I currently use is called 'M2' so its not the same one I'm using but I'm just worried what these things are and how they got there. They both apparently have 1gb of data but I cant find anything inside them other than a few older personal files in the 'M.dmg'. I transferred my old computer on to this one but I've never seen this Deleted Users file before just worried about touching/deleting them if they're important. I have this computer for about three years now, not sure why I've never seen this.

Sorry I rambled, basically I'm just worried what these are exactly. They both have about 1gb of data but I cant see anything other than a few things in the old user .dmg and I have no idea what aspnet.dmg even is...What are they? Should I delete them? & Why do they seem to have pretty much nothing but say its 1gb each? I'm just confused, Thanks!