"As a developer, our primary goal is always to develop an application that works properly, but we should be focused on writing clean and safe code as well. In this section, we will be talking about clean and safe code a lot, so let's look at what we mean by these terms.
Clean code is code that is very easy to read and understand. It is important to write clean code because any code that we write will need to be maintained by someone and that someone is usually the person who wrote it. There is nothing worse than looking back at code you wrote and not being able to understand what it does. It is also a lot easier to find errors in the code that is clean and easy to understand.
By safe code we mean code that is hard to break. There is nothing more frustrating as a developer than to make a small change in our code and have errors pop up throughout the code base or to have numerous bugs pop up within our application. By writing clean code, our code will be inherently safer because other developers will be able to look at the code and understand exactly what it does...."
- Swift Protocol-Oriented Programming, Jon Hoffman
