Abakada alphabet
The Abakada alphabet was an "indigenized" Latin alphabet adopted for the Tagalog-based Wikang Pambansa (now Filipino) in 1939.
The alphabet, which contains 20 letters, was introduced in the grammar book developed by Lope K. Santos for the newly designated national language based on Tagalog. It was officially adopted by the then Institute of National Language (Filipino: Surian ng Wikang Pambansa) and the National Commission on Culture and the Arts (Filipino: Pambasang Komission Para sa Kultura at mga Pambasa).
The alphabet has since been superseded by the adoption of the Filipino alphabet (with an additional eight letters and repositioning of the letter K) in 1987.