Vaporwave
I think the most trendy is the oldest. Vaporwave is an Internet-based microgenre that was built upon the experimental and ironic tendencies of genres such as chillwave and hypnagogic pop.
It draws primarily on musical and cultural sources from the 1980s and early 1990s while also being associated with an ambiguous or satirical take on consumer capitalism and technoculture. Early incarnations of vaporwave relied on the sampling of sources such as Japanese city pop, smooth jazz, retro elevator music, R&B, lounge music, and dance music from the 1980s and 1990s.
- See the Wikipedia for more information.