@prophamoon it's a bit like twitter but with multiple timelines to see
home: this is all the posts from the people that you follow
local: this is all the public posts from those who also use the particular instance you're on (in this case everyone else with an account on computerfairi.es)
federated: this is all the public posts from everyone local as well as those using other fediverse instances (that are visible to the local instance, known as being 'federated with')
@prophamoon if you want to know something more specific, feel free to ask! though i might be a bit rusty, it's been a hot minute since i used mastodon regularly