Nearly every application that you will build will need to implement collections of data in some form or another. This could be anything from a database query that returns multiple records to a set of dates in a calendar. In this chapter, we're going to walk through how to work with collections in a Ruby program, including arrays and hashes. After going through this chapter, you will be able to do the following:

• Demonstrate how to work with data collections in Ruby
• Explain how to work with the array and hash data structures and how to add, edit, and remove items from collections