What are the two types Swift?

Excuse me, but I'm curious about something mentioned in the paragraph. It talks about Swift, but I'm not entirely clear on what the two types of Swift are being referred to. Could you please elaborate on that? Are we discussing the programming language Swift or perhaps something else entirely? If it's the programming language, I'm unaware of any distinct types within it. However, if there's a specific context or usage that the paragraph is referring to, I'd be grateful if you could clarify it for me. Thank you in advance for your explanation.