Why Does This Loop Take Seconds? Your Language's List

A loop over 100,000 orders takes seconds, and one call in it is why. Meet your language's list, the growing array under five names, and read its cost card before you pick a method.

Updated

Cheat sheet: Why Does This Loop Take Seconds? Your Language's List
Category
Data Structures
Level
Apprentice
Tags
Array (javascript), ArrayList, data structures, Dynamic Array, List (python), List<T>