Two machines are used in each Mega Millions drawing. The model used for Mega Millions is the Criterion II, manufactured by Smartplay International of Edgewater Park, New Jersey. The balls are moved around by means of counter-rotating arms which randomly mix the balls. Individually, the five white balls, several seconds apart, drop through a hole in the bottom of the mixing drum.
Every jurisdiction has its own law on winners remaining anonymous. Some jurisdictions are required by law to provide the winner's name, city of residence, game won and prize amount to any third party that requests the information. Other jurisdictions allow winners to create trusts to shield their names from the public, or otherwise claim prizes anonymously. Check with your lottery to see if taking a photo of the winner is required and what its rules are on prize claims. Even if you keep your identity secret from the media and the public, you will have to be known to the lottery so officials can confirm you are eligible to play and win, as well as other legal requirements.
And of course, if non-US residents are eligible to buy the tickets, they are also eligible to claim the prize money should they win. However, be aware that the rules covering taxes and withholding vary depending on where you live. Countries outside of the United States might have different procedures. If you do win, be sure to consult with a tax professional for more information.
The two different methods, both offer you, the player, the same user experience and the only difference is in the back end of how the online lottery ticket provider works. The two methods that online lottery sites use differ in one key way; They either have agents and employees all over the world that physically purchase tickets on behalf of clients or, the more recent phenomenon is when companies essentially take out an insurance policy on every ticket which is tied to the size of the jackpot. This is the difference between you playing the lottery online and betting on the lottery online*. In the latter option you are, de facto, not playing the US Powerball online but rather you are placing a bet with an insurance company on the outcome of the corresponding Powerball draw.