OPM started becoming a name people used in the 1970s, when Filipino musicians wanted listeners to know that not all the music on the radio had to come from America or Britain. They could write their own. Today, OPM is everywhere: in shopping centres, on the radio, in karaoke machines, at school events and family parties.
Some OPM songs are sung in Filipino (also called Tagalog), some in English, some in Cebuano (a language spoken in the middle of the country) and some mix the languages in the same song. A favourite OPM trick is to drop one English word into a Filipino verse, just for fun, or the other way around.
Filipino children grow up surrounded by OPM. Many learn the words to family favourites before they can read, because their parents or grandparents play them in the car and at home. School concerts almost always include at least one OPM song, performed by the whole class.
The Philippines has produced singers who are famous all around the world. Many of them say they started by singing OPM songs at family karaoke nights when they were children, picking up a microphone before they could really reach it.