An array is a data structure consisting of a collection of elements (values or variables), each identified by at least one array index or key. ... Array types are often implemented by array data structures, but sometimes by other means, such as hash tables, linked lists, or search trees.
Learn more on W3schools:
https://www.w3schools.com/angular/angular_expressions.asp
Also view the whole Tutorial on my Playlist:
https://www.youtube.com/playlist?list=PLo_-PBU3yTF_-4MUD-h779xZjOXmIumPf
