   Tiles sets.
  Okay, let's get out of the way the usual "I'm new here" and say hi.Hi.Now that's done I have a question about "tiles", I know that they build up a level in a lot of older console games and understand that setting some tiles as "walkable" but the burning question is how does these tile sets work? Is the "Stage" created first then the tiles are added in or does a programmer slowly and carefully place each and every tile into it's "place".Thanks in advance.   
  Welcome to the forums!Generally, yes, you will have a "stage" that loads in data specifying which tile goes where. The programmer usually doesn't have to place these tiles by hand, but it's not rare for a text-based format to be used and written by hand for small games. In many cases, people will make map editors do this work automatically and simplify the process greatly.   