Tanaka’s daughter got married to a foreigner.
A drunk foreigner tried to pick a fight with me on the train.
Leg length is quite different between Japanese people and foreigners.
An "outside person" is a foreigner. This word is fairly common, though it's not super polite, either. It's okay most of the time, but it can be used derogatorily depending on the situation. The more polite version is 外国人 (outside country person) but you won't learn that until you learn the kanji for 国.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
Since 人 has two on'yomi readings, you can remember that for this word it uses じん because foreigners like to wear jeans (じん).