[quote=Chancellor Kremlin]Why does it change? What does остановка mean?[/quote:lvy4uu3d]Originally Posted by "Оля":lvy4uu3d
There's no explanation. We just use остановка for a bus. It means "a stop". Станция refers to the railway, and that's how it is.
But станция has also other meaning, for example "станция переливания крови" (blood transfusion post).