💡 Which declaration form should I use?

Use a long declaration when you can’t know what data to store beforehand, otherwise, use a short declaration. Use the multiple declarations when you want to define multiple variables together or as a hint for code readability that the variables will be used together.

You can’t use short declarations outside of functions including the main function. Or: you will meet with this error: “syntax error: non-declaration statement outside function body”. Not good.