Niedrig vs. gering vs. wenig!
when to use each?
"niedrig" (adjective) = "low = not high": a table, a house, the level of water in a river, my wage, a percentage, a number, a Duolingo level
"gering" (adjective) = "low = not much, minor": damage, losses, deviations from the average, visibility (e.g. in fog), probability, lead ("he won the race by a short lead"), share ("only a small share of people are rich")
"wenig" (adverb / pronoun) = "little = not much": money ("I don't earn much money"), time ("I have little time"), content ("the cake contains not much chocolate"), taste ("you have / the yoghurt has little taste"), sleep ("I didn't get much sleep"), beer ("I didn't drink much beer")
Sometimes they can be used interchangeably, e.g. with (here: a suitcase's) weight:
"Der Koffer hat ein geringes/niedriges Gewicht; das Gewicht des Koffers ist gering/niedrig" = "low weight"
"Der Koffer hat wenig Gewicht" = "little weight" (not "das Gewicht ist wenig"!)