Until the first half of the 20th century, Tagalog was widely written in a variety of ways based on Spanish orthography. When the national language was based on Tagalog, grammarian Lope K. Santos introduced a new alphabet consisting of 20 letters called ABAKADA in school grammar books called balarilà:


A B K D E G H I L M N Ng O P R S T U W Y.
In 1987 the department of Education, Culture and Sports issued a memo stating that the Philippine alphabet had changed from the Pilipino-Tagalog Abakada version to a new 28-letter alphabet:


A B C D E F G H I J K L M N Ñ Ng O P Q R S T U V W X Y Z


to make room for loans, especially family names from Spanish and English.