Splitting functions into synchronous and asynchronous kinds forces that distinction into every piece of code a programmer afterwards writes.

Drawn from what Bob Nystrom said

What this subject means

design How things should be made and judged: what makes a design good, who should do the designing, and what an interface is for.

What Bob Nystrom actually said

Do you hold this korrent?Do you also believe this?

Shared subject first, then similar wording. They may agree or disagree.