How much should I scale my terrain and objects?

I begin a game and I don’t know how much to scale the terrain. I know one unit on the grid in Unity is one meter. Should I put a value like in reality, for example if my terrain is big as a soccer field, maybe i should put like 100 meters or so?

The only way in which one grid in unity is one metre, is where the physics engine defines gravity as ‘9.81’. The grid is, in fact, completely dimensionless! If you wanted the grids to instead mean ‘10 metres’ you could do that, and set gravity to 0.98 so that physics acts as expected.

For the sake of simplicity, one would usually set the scene so that one grid == one metre, but it’s not always the best way to do things- for example, if you made a large-scale RTS, you might want to keep it smaller. Remember, Unity is completely dimensionless- as long as all your sizes scale properly, it doesn’t really matter how big things are!