What organ is always found at the core of all animal cells and plant cells

If you are talking about organelles, instead of organs, then the answer is the nucleus. There are no organs in animal cells or plant cells.

Nucleus is the core of both animal and plant cells

Are you asking about a street map usage  if so here is your answer  a street map for a very limited area could simply be a bit map or a .jpg image.  but a more general map would probably store the streets as vectors.  but you shouldn't assume that there is one way to do it