Street circuit
A street circuit is a track laid out on public roads that are closed for the event, rather than a permanent racing facility.
They share a set of characteristics: walls instead of run-off, a bumpier and dustier surface that improves across the weekend as rubber goes down, and very little room to overtake.
That combination makes qualifying disproportionately important — Monaco is the extreme case — and it makes safety cars far more likely, since a mistake usually ends against a barrier rather than in a gravel trap.