javascript-arrays

Question 1

What are arrays used for?

Answer 1

Arrays are used for storing ordered values. The indices have values that start at 0 and increment by 1 as the array stores more values.

Question 2

Describe array literal notation.

Answer 2

Array literal notation looks like so: var threeValues = [1, 2, 3];

Question 3

How are arrays different from “plain” objects?

Answer 3

Arrays are different from “plain” objects in the fact that they are a specific type of object. All array key values are numbers, starting with 0 as the first key and increasing by one for each subsequent key.

Question 4

What number represents the first index of an array?

Answer 4

The number that represents the first index of an array is 0.

Question 5

What is the length property of an array?

Answer 5

The length property of an array carries the value of the number of items in an array.

Question 6

How do you calculate the last index of an array?

Answer 6

To calculate the last index of an array do this notation: arr[arr.length-1];