A: The ballot paper referred to the terms of a deal that had strictly speaking already been taken off the table, but in a nutshell Greeks were asked whether they would accept more austerity in order to keep rescue finance coming into the country.
They said No. It means we - and the European establishment - now know that the Greeks are prepared to face the unknown rather than accept more cuts.
Q: So what happens next?
A: Greek Prime Minister Alexis Tsipras will return to Brussels today to reopen bailout talks with his anti-austerity mandate hugely boosted. The 60pc backing for his preferred No vote means the Syriza leader won support from way beyond his own core voters.
Taken together with the results of last January's election, it gives him effectively a double "anti-austerity" mandate to negotiate with the rest of the eurozone, though in reality not much else. Mr Tsipras now has more authority to push for the same concessions he was after before talks with the European institutions broke down last month, but his country is still broke.
And it still takes two sides to talk. Unless the referendum results prompt a change of heart on the other side of the table - including for German Chancellor Angela Merkel - it could well be a case of going straight back to stalemate.
French President François Hollande looks more likely to see the results as a reason to soften his stance, and potentially to break with Ms Merkel. The two leaders are meeting today.
If Greece's "partners" don't show signs of compromise today then we can take it that Greece is heading for a euro exit, but it will be the rest of the euro area that has to do the pushing.
Q: So the No vote means it's back to the negotiating table. But what are the talks about?
A: The round of talks starting today are about the same thing they were about a week and a half ago. Greece has run out of money and needs help.
Its government needs access to as much as €50bn, mainly to keep on top of its debt repayments over the coming years. Before the latest lurch in the crisis, Greece was actually taking in enough in taxes to pay for day-to-day services - excluding loan repayments - but after the banks shut for a week that may no longer be the case. If Greece secures a new deal, it will remain on the critical list. Without a deal, Greece will renege on more and more of its external debts, and its banks will be unable to access the euros needed to maintain economic activity.
Q: Are those Greek banks open or shut?
A: Shut, but due to reopen tomorrow. The Greek Central Bank last night asked the European Central Bank (ECB) to increase the amount of emergency funding available to its banks.
A decision on that will be taken by the board of the ECB as early as today. In theory, that will be a non-political decision based on factors such as the strength of the Greek banks. In reality, it will be a highly political and potentially contentious decision.
If the ECB decides the Greek banks are insolvent, it can stop further emergency loans and that would - to all intents and purposes - drive Greece out of the single currency. Potentially very rapidly - within days. That is a big call for unelected central bankers.
Q: Hang on, this is all starting to sound like nothing has changed?
A: The Greek debt crisis is still deadlocked, that is true. The good news, such that it is, is that the Greeks themselves are less polarised than many had feared. So whatever happens now, including a possible Grexit, at least the people there have taken a calculated decision that this is something they are prepared to face. That may have been Mr Tsipras's calculation all along.
Q: What about us, is there a risk to Ireland from this?
A: In the immediate term, Ireland looks to be reasonably well sheltered from the direct impact. The financial markets will certainly be weaker today, including the euro, in all likelihood.
Investors will pull cash out of riskier assets, such as shares and some bonds, and shift them into the dollar and very safe government bonds, like America's and Germany's. Our bonds are seen as neither super safe or very risky, so could end up largely left alone. Spanish and Italian borrowing costs will rise, and in the end that means investors will look to make money out of lending in general - which is bad for the flow of credit.
But we don't do a lot of business with Greece and, in the short term, a weak euro benefits Irish exports. The longer term implications for the euro will depend how the Greek situation plays out over months rather than days. A Greek exit will damage the European economy, which is fragile anyway.
Q: Could the rest of the euro area carry on regardless if Greece leaves?
A: If Greece leaves the euro, there will always be a niggling feeling that others might some day follow. Compare that to the US dollar which can survive just about any kind of crisis intact.
To compensate, a Greek exit might spark a push for greater integration among the remaining euro member states - including closer budget ties and common bonds. But political resistance to any such moves will now be greater than ever.