I offer this definition only as my basic understanding of what Prose is:
'Literary writing that cannot be defined in terms of other prose literature forms (short story, autobiography, essay) but which displays literary qualities. Includes creative, imaginative writing such as Liam Davison's Land Sounds and extended prose works in the travel, historical, humour and satire genres, such as Nicholas Jose's Black Sheep, Ernestine Hill's The Territory, Barry Humphries's Bazza Pulls It Off.'
As part of the standard English course at school we read Prose (and Drama, Novels, Poetry etc).
Maybe it's an Aus thing which follows on from the received traditions from England.