system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What exactly are surveyors doing when they're looking through those tripods??

I see them all over the place, with their yellow jackets looking through those tripods and I have no idea what the hell they're measuring or why they're measuring it. HELP!
gpt
They're looking at a stick through a little telescope to measure the angle at which they can see the mark on it. They do this lots and lots of times in lots and lots of places and use the results of this triangulation to create a height map.