Collections

Hello,

In this lesson, we will learn about collection types in Swift, which is one of the most important topics.

So let's start.

There are 3 collection types in Swift.

Array → Sequential collection types.

Set → Unordered and unique collection types.

Dictionary → Collection Types without order and in key-value pairs.

Whether our collection types are immutable or mutable is determined by our definition.

If we define it with a let statement, it will be immutable, while it is mutable if we define it with var.

If the value we defined will not change afterwards, using let will provide a performance advantage for the compiler to run more optimized.