I am currently DM'ing Storm King's Thunder. The book contains many maps, and each of them has a DM version and a player version. I am wondering if other DMs/GMs show their players these maps. For example, an overhead map of a town. I am split on this. On the one hand, I know my players would like to see it, and it would probably help them in many ways. But on the other, I am thinking that the player's characters would not have an overhead map of the town. So, to me, it makes sense to not give the map to the players. Any thoughts on this?
Consider it from the standpoint of a simulation.
D&D, at its heart, is a simulation. Often you simulate combat, or the use of skills, etc. The simulation has several "modes." In combat mode, you are simulating time in blocks of a few seconds, during exploration, the unit of time expands and so does the way you communicate the players' surroundings to them. When you simulate the use of the climbing skill, you don't have the player literally climb something (...usually). Well, the same goes for simulating their characters taking in information. When the character reads a book, do you make them literally read a book? No, you give them the gist of it plus the important points.
When you place a town map in front of the players, you could look at it as: "I am handing them a bird's eye view of the whole town." But a more constructive way to look at it is this: by presenting them with the map, you are simulating everything they observed, heard, and smelled as they approached the town, entered its gate, and wandered around for a while. And remember that topography matters. There may be a hilltop inside the city from which the PCs could literally see most of what's on your map. You should feel free to black out parts of the map that are not publicly accessible (like inside the castle walls). If they haven't been down a particular street, the fact that they can see that street on the map represents the fact that they could walk or look down that street freely if they so chose. The information on the map can also simulate what they might learn from conversations with passersby--like a merchant who offhandedly mentions that the north end of the city is a nice area with broad streets and lots of standalone villas, or a child who tells the PCs about a gladiator arena nearby. Then when they tell you their characters are going somewhere with a purpose, you switch to encounter mode.
There Is No Right Or Wrong Answer
There really isn't. It's very contextually dependent on whether the PCs are going to experience some real-time need to access that information or are going to be materially surprised by it in some way. An important side-issue and matter of personal style is that concealing a map often highlights the sense of unfamiliarity to the players, whereas giving them a map will heighten their sense of familiarity-- your intent as GM matters, here, but again this is a matter of style. Finally, your and your players' tolerance for the relatively slow progress of room-by-room exploration, as it transfers over to street-by-street exploration matters.
For a dungeon-crawl situation, I (and I think most GMs) conceal some or all of the map, either revealing slowly as the players go along or even making them map it out old-school.
For an unfamiliar city situation, if the players have shown any curiosity at all and talked to any NPCs at all, I'll often given them a low-detail hand-sketch showing the major sections of the city. I can imagine some situations where I might not-- if part of the adventure hinges on them wandering into some sort of bad territory, I'm not exactly going to give them a map saying "Bad territory!" If they need to find some place that is not a major well-known feature, I'm not going to label that for them. But my personal experience is, it won't hurt much, and it will alleviate some of the slow-paced exploration that I'm not a big fan of.
For a ruined city, well, this is often more of a dungeon crawl situation where the PCs probably don't have convenient NPCs to ask about, and the exploration is assumed to be dangerous. So here, I'd gravitate to the slow reveal again.
It depends on how well acquainted with the location they are.
In your example of the town, this GM would not give their players a map immediately, but if they stayed for a few days and actively spent time learning the city, I would give them a copy of the map.
This follows the same logic as maps of dungeons. You wouldn't give them a map of the place the moment they walked in, but you would reveal pieces as they go room by room, and if they have the opportunity to safely explore the whole place, you could just hand them a copy of the map.
Thus, maps become a form of reward just as much as treasure or reliable contacts.