The Abakada alphabet was an "indigenized" Latin alphabet adopted for the Tagalog-based Wikang Pambansa (now Filipino) in 1939.[1]
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.[2] 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).[3]
The alphabet has since been superseded by the adoption of the Filipino alphabet (with an additional eight letters and repositioning of the letter K) in 1987.