Hubs allow you to have multiple pages for different projects. Say you have a solo project, a band, and run a label. Each of these can be represented as a different Hub. Hubs can also be used to make playlists by reposting tracks to Hubs.
There’s a bunch more that Hubs can do - you can read more about them here: https://mirror.xyz/ninaprotocol.eth/5NZv9NduBNNrUh195pvFDqToinZALbaWFXguXxrtR4k