With Objective-C, we were able to mark different sections of the code with the help of the #pragma mark directive.
Swift exposes three straightforward keywords you can use in your code base. Those markers appear in the symbols list dropdown, which you can bring up by default with the Ctrl + 6 shortcut:
// MARK: renders with a blue list
// MARK: - (inserts an empty line)
// TODO: renders with a blue bullet list
// FIXME: renders with an orange band-aid