The Characters

Baybayin is an abugida — each consonant character carries an inherent /a/ vowel. A small diacritic mark called a kudlit above or below the character changes the vowel to /e·i/ or /o·u/.

Vowels (Patinig)

a
e/i
o/u

Consonants (Katinig)

Classical pre-colonial Baybayin — no final consonants.

ka
ga
nga
ta
da/ra
na
pa
ba
ma
ya
la
wa
sa
ha

The Kudlit Marks

Only the vowel-changing kudlits existed in the classical script.

Kudlit above → E / IPosition: above
Kudlit below → O / UPosition: below