Public key cryptography. The client has to satisfy both the domain control challenge, and sign a nonce provided by the CA. The domain control challenge establishes control over the domain. The signed nonce provides client identity verification.

https://letsencrypt.org/how-it-works/

This is why I indent with tabs, and then do alignment/tabulation/etc with spaces. Precise relative-positioning of elements is maintained, but the user can set the tab width to whatever they desire without breaking anything except maximum line width.

It works great, and I even change the tab width periodically myself depending on what exactly I'm doing at any one time, as it lets me change focus from overall program structure to detailed tight blocks without reformatting everything.

That isn't what autopilot in an airplane means at all. Stop spreading misinformation.

Not really. It's a point-to-point link, which means you have two directional antennas pointed at each other. The equipment manufacturer will have a done a link budget over distance, including free space propagation loss, atmospheric losses, and rain fade.

As a Canadian that recently moved the US, the system here is utterly ridiculous and broken. I never know when I should swipe vs insert the chip, I have never been asked for a pin, sometimes I have to sign and sometimes I don't (there doesn't seem to be a clear limit), and there's no tap-to-pay. It's that last part that was killer; I used tap-to-pay for 90% of purchases in Canada, with chip+pin being the remaining 10% of larger purchases like electronics.

There's also an obsession with literal cash, here. People see it as the default, whereas in Canada, cash tended to be a fall-back for most people.

It's truly bizarre. I find it much more annoying to pay for things here.

Better yet, do it in the client at no CPU cycle cost to Dropbox, and also reducing data transport. Dropbox controls the desktop, mobile, and web clients, so this would be easy to do, and could revert to server-side translation from LEP to JPG for e.g. API clients etc.

Please stop referring to Tesla's autopilot feature as "self-driving". It is not. At best, it is an adaptive cruise control with lane keep assist and some basic collision avoidance capability.

We don't know what the right path to fully autonomous self-driving cars is, but that is almost certainly the long-term solution. I expect the legislative issues to be far more difficult to resolve than the technical ones, and we'll have enough difficulty with it as is; we don't need people muddying the waters by claiming Tesla's autopilot feature is anywhere near an autonomous self-driving vehicle controller.

Don't forget water; it will be the most valuable space resource for the foreseeable future. You can use it as propellant, you can make rocket fuel out of it, it's necessary for most chemical processes you may wish to setup, you need it to live (if you are sending people), you can use it as a radiation shield, ... it's a pretty amazing resource.

To be fair, the first one they successfully landed was always destined to end up as a lawn ornament.

The problem with parking isn't that there's no parking, it's that there's no parking sufficiently close to where you want to go that you don't mind walking the remaining distance. With self-driving cars that can drop you off then go park themselves, and be summoned when you are ready to leave, this won't be a problem.

That was originally true, but the order kind of ended up getting swapped: SpaceX has already successfully landed a Falcon 9 first stage on land, back at the launch site (different pad, but nearby): https://youtu.be/1B6oiLNyKKI

I don't hear any presidential candidates demanding unwarranted access to my private, encrypted information to tackle any of those issues.

Here is a perfect example: Toronto Games Critic [Veerender Jubbal] Falsely Linked with Paris Attacks .