Once I got past the basic Hello, World! beginner applications, I quickly began to realize the shortcomings of variables, especially with the Mad Libs-style applications that I was starting to write. These applications requested that the user enter numerous strings, which resulted in the creation of separate variables for each input field that the user entered. Having all these separate variables quickly became very cumbersome. I remember talking to a friend about this, and he asked me why I was not using arrays. At that time, I was not familiar with arrays, so I asked him to show me what they were. Even though he had a TI-99/4A and I had a Commodore Vic-20, the concept of arrays was the same. Even today, the arrays found in modern development languages have the same basic concepts as the arrays I used on my Commodore Vic-20. While it is definitely possible to create a useful application without using collections, such as arrays, when used properly collections do make application development significantly easier.

In this chapter, we will cover the following topics:

• What an array is in Swift and how to use it?
• What a dictionary is in Swift and how to use it?
• What a set is in Swift and how to use it?
• What a tuple is in Swift and how to use it?