JavaScript Arrays

Question 1

What are arrays used for?

Answer 1

Arrays are used for storing a list of values, sorted in order and hold numeric value, that are related to each other

Question 2

Describe array literal notation.

Answer 2

Declare a variable and the values are separated by commas , and are all within a pair of square brackets []

var Array = [‘String’, ‘2’, ‘False’] (String, Number, Boolean)

Question 3

How are arrays different from “plain” objects?

Answer 3

Arrays are held in square brackets and do not hold key:value pairs.

Arrays indexes and index values

Question 4

What number represents the first index of an array?

Answer 4

You start counting at 0

Question 5

What is the length property of an array?

Answer 5

array.length will return the length of the array

[one, two, three] has an array.length of 3

Question 6

How do you calculate the last index of an array?

Answer 6

array.length - 1 will return the last index of the array