(A)Yes: a printed/hard copy.
(B) Yes: an electronic copy.
(C) Maps? You have maps?…
(D) No, the DM has a map hanging on the wall/lays it out on the table during game sessions for us to view.
(E) No, we learn about it as we explore, with maps provided as exploration takes place.
(O) Other? Please share!
This can apply whether you run a homebrew game world, or a commercial setting. A Gazetteer can be used to plant adventure seeds, mentioning ruins, lost civilizations, monster lairs, etc. It can also contain house rules for the DM's game.
So… Do you, or does your DM, provide such to players when they join the game? This can be printed materials, PDF's, or other electronic files. They may include maps, or not; they may include House Rules (HR), or not. Racial/class limits may be described, etc.
In the 1980's, I wrote up a Gazetteer, with a photograph of my game world map attached to the 3-hole, pocketed folder's cover, which I handed to new players; it had a label printed, and attached to the cover, above the photograph, with title. Back then, I typed them up, then I made photocopies of them, punched them, and put them into folders. Now, I do it by PDF (much cheaper).
I have made up plenty of hex maps, using different software applications, over the years. I make them in color, and I include these, as well as other stuff. I include short write-up's on the religions of the game world, but only for players running Clerics. They get a free 2e NWP within their race's Religion (they get a basic knowledge write-up of the gods in that race's pantheon of gods, their Spheres of Access, Holy Symbol, short description of the god's influence, but nothing more).
I give a rundown of the geography of the world, so they know a little bit about each city/area of the continent where the campaign will be based (the rest of the planet is left undefined, for them -- I have it mapped out, but largely undeveloped). I seed it with historical references to the Ancients, ruins, etc. I even include a little bit of history about the world.
I include my HR's: Magical Research rules, Illusion magic rules, if they are playing a Mage; and anything else I deem necessary.
I find this helps my players immerse themselves into my game world's culture. Over time, it becomes more real to them. It helps lay a game world foundation we can all build upon, as a group.
For me, it is (A), (B), and (O): I am working on a d20 globe of my game world. Need to get back to it, to paint the continents, add labels to the seas, oceans, continents and islands. Bigger project than I had hoped…
How about you, or your DM? Cheers!