There are three genres that were invented in Australia:
People around the world may be familiar with Pub Rock thanks to a little known band called AC/DC. They and many other rock bands were touring at a time when the live music scene revolved around the Aussie Pub. As a result, the music, and particularly the lyrics, reflected this.
Bush Ballads are the lesser known and more antiquated Aussie music style. Think of it as folk music written by people who loved sheep a bit too much. As a mix between love of rural Australia, folk music, country music, and oldy time-y nostalgia, the genre is less popular now than when gramophones were a thing. That isn’t to say that Bush Ballads had no influence, as Waltzing Matilda is regarded as the unofficial national anthem, and some songs have gained international audiences from cover versions (see Dr Hook example below).
Indiginous music as it stands today would generally be better referred to as fusion. This is because it combines traditional Indiginous musical styles and instruments and fuses them with other genres (rock, hip-hop, rap, country, etc). What makes it such an Australian genre is the cultural themes and lyrical content, which is very unique.