Finnish Is Not Related to Its Scandinavian Neighbors
Finnish belongs to the Finno-Ugric language family, distantly related to Estonian and Hungarian, rather than the North Germanic languages spoken next door — so its vocabulary and grammar look unfamiliar even to Swedish or Norwegian speakers. Its spelling is highly consistent, though, so words are pronounced almost exactly as written.
Vowel Length Changes Meaning
Doubling a vowel or consonant, as in "Hyvää" versus a shorter form, lengthens the sound and can completely change a word's meaning, so the pronunciation guides here are only approximations. Listening to native audio helps a lot with getting the rhythm right.
Frequently Asked Questions
Is "Hei" or "Moi" more common?
Both are extremely common. Hei feels slightly more neutral while Moi feels a touch more casual, but either works fine for everyday use with people your own age.
Is Finnish hard to learn for English speakers?
Its grammar, with extensive case endings, takes some adjustment, but its very consistent spelling-to-sound rules make pronunciation more predictable than in many other European languages.