The text has a few typos: an extra letter, a missing letter or two swapped letters. Don’t retype it — move with ← →, jump a word with Ctrl + ← → (Option on a Mac), go to the start or the end with Home and End, then delete with Backspace or Delete and type what is missing. Every key is a stroke, like in golf: par is the shortest route, and fewer strokes earn more points. Scalpel marks the errors in red; in Proofread you find them yourself, and Enter shows them for 5 strokes.