Y’all have first past the post / winner takes all, don’t you?

Nope. Instant-Runoff Vote, where we rank preferences. It's much better.

• https://en.wikipedia.org/wiki/Electoral_system_of_Australia

• ncase.me/ballot/ has a neat interactive visualisation of different voting methods.

Labor, coalition, independents, etc. what kinds of parties are these?

The Coalition is a coalition of allied parties, not just one party. Generally speaking, it's the Liberal Party and the National Party. Now, if you're used to American political media, you've probably learned an incorrect definition of 'liberal' - it doesn't actually just mean 'progressive', liberalism is an ideology focusing on the ideal of liberty, and most parties in modern liberal-democratic countries are liberals, whether they're classic liberals (think US Libertarians), progressive liberals (think a Green party) or conservative liberals. The Liberal Party of Australia are conservative liberals, and they've been mirroring some of Trump's rhetoric and US Republican Party ideas like the DOGE, and rationalising new coal power plants. Australia apparently didn't like that.

Labor were historically a social democrat party representing the labour movement and unions, but has drifted further away from that and is now considered either the centre or centre-left party.

The Greens are the third biggest, a populist progressive party, focusing on issues like environment and climate, social justice and housing.

Independent candidates are independent, they aren't in a party. Some have left their old parties, some were never in one.

I thought Albanese was a “cunt” yet his party seems to have won again?

Since when has that stopped politicians from winning?

What’s going on?

The Liberal Party faceplanted, many of their voters swung to Labor. Others will have chosen smaller parties, but Labor and Coalition each had about 33% of the primary vote in the past few years with Greens and One Nation down somewhere around 10% so Labor was clearly the most likely to win this year.

Interestingly, unlike the House of Representatives which election coverage has focused on, there is still a crossbench in the Senate, it looks like Greens will still have around 11 members there, forcing Labor to appeal to them in order to pass bills in the Senate.

These are generalisations, there are some technicalities I've avoided.