system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:What's the difference between highways, freeways and expressways?
gpt
The main difference would be between freeway and highway. A freeway is guaranteed not to have at-grade crossings like pedestrian crosswalks or intersections like one would need a stop sign or traffic signal for (albeit there are some stop/go traffic meters in place to help control traffic), while a highway is allowed to have these things.

An expressway is generally a multi-lane highway that allows more traffic to flow faster, but certain area's have more specific definitions for them.

EDIT: As noted in below answers: Freeways *are* highways, but with less things allowed on them.