Imagine you’re standing on a double-track section. From your perspective, the track on the left leads away from you, the track on the right leads towards you.

Imagine you’re standing on a double-track section. From your perspective, the track on the left leads away from you, the track on the right leads towards you. As to why: having this uniformity is useful in placing, eg, signals (which face in one direction). Much more confusing in railways is which track is the “up” line and which is the “down” line.