That heavily depends on what you mean by writing music. Musescore (the software, not the website) is pretty good for writing notation, and open source.
If it’s more about producing a track, there’s Ardour, also foss. If you wanna pirate an “industry standard” daw, there’s FL Studio and Ableton, I guess.
Depending on what you want to do exactly, there might be a lot of other software that fits the bill.
That heavily depends on what you mean by writing music. Musescore (the software, not the website) is pretty good for writing notation, and open source.
If it’s more about producing a track, there’s Ardour, also foss. If you wanna pirate an “industry standard” daw, there’s FL Studio and Ableton, I guess.
Depending on what you want to do exactly, there might be a lot of other software that fits the bill.