The preprocessor directive allows the compiler to understand that we are adding a library a previous programmer has included to allow the code to work.
An Expression statement is what code we have used that generally has a semicolon at the end of it
Whilst a Declaration statement has the hard code information that we would write in Visual Studio Code
The return statement is seen as just having a return and a value as well as a semi colon letting us understand whether something has worked successfully or gone wrong in our code.