Arrays and array-like objects

Overview

This module covers both arrays and various array-like objects that are used extensively in JavaScript in manipulating the DOM.

If you are already comfortable with the programming concept of arrays or sequences, please proceed to the next step.

Brief review of programming concepts: arrays

Just like a string is a sequence of characters, it is possible to store a sequence of numbers, strings, or other types of data. Each individual value in a sequence is an item or element, and can be accessed by its index or position. Positions are usually numbered starting from zero.

Sequences that are mutable can be changed, for example, by adding or deleting elements.

A function with a sequence as input might create a new sequence or change the input sequence.

Mutation can lead to aliasing, a situation in which two different names are used for the same data.