URLS stored in the post field.

[Ocean West]

i am seeing various styles urls for attachments / links in my post table post field:

Examples

https://invisioncommunity.com

and in some cases the site URL?

what should be the proper url for the links?

and shouldn't internal links if someone copies and pastes a link to another post shouldn't the url be replaced with the abstract string so that should the url change or or the path change then the embedded links would continue to work?