Correction: Unicode strings are made up of scalar values, not code points. The difference is that accursed mess that UTF-16 foist upon us, surrogates;oU+D800–U+DFFF are code points, but are not valid scalar values and cannot occur in Unicode strings (even if things like JavaScript are stupid in allowing potentially-malformed UTF-16, which is incompatible with Unicode, and Python similarly stupid in having strings that are not Unicode but are instead sequences of code points).