Parallel
In Parallel
noun, verbal noun, の adjective
Line up everything in a row. When you do that, they're all in parallel.
並列 is specifically used to describe items being arranged in a parallel way, like in parallel circuits or when vehicles are parked parallel to each other.
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.
今日は学校で、直列回路と並列回路について学びました。
Today at school we learned about series circuits and parallel circuits.
その駅では、特急電車と各駅電車が並列して停車していた。
At that station, the express train and local train were stopped side by side.
私はテレビを見ながら家事をしたり…みたいなマルチタスクの並列処理が苦手です。
I am not good at doing multiple things simultaneously, like doing housework while watching TV...