About Finnish letters
Finnish uses ä and ö constantly, å only in Swedish loanwords and names, and š and ž in some foreign words.
The Finnish layout is the same as Swedish, with å, ä, ö to the right of P and L.
On a Mac, Option+U then A or O gives ä and ö.
Finnish letters: names and codes
Every special letter in Finnish, with the Windows Alt code where one exists, the hex code to type in Word followed by Alt+X, the Mac shortcut and the HTML entity. Click a letter to copy it.