I don't know of any documentation off the top of my head but currently there's
User links: @marsara9@lemmy.word
These will translate to https://<your instance>/u/marsara9@lemmy.world
assuming your not on lemmy.word. If you are it will just be https://lemmy.word/u/marsara9
.
And community links: [!fediverse@lemmy.world](/c/fediverse@lemmy.world)
These will follow the same pattern but will have /c/ instead of /u/.
There's been proposals to add others but that's all that exists at the moment.