

An Introduction to the Mechanics of Bitcoin - spicyj
https://www.khanacademy.org/science/core-finance/money-and-banking/bitcoin

======
joshuak
As a cypherpunk, when I first heard of bitcoin I was incredulous. But after
many months of research and experimentation I became satisfied that the
bitcoin protocols don't have any _obvious_ flaws. God how I wish I could have
saved some of that time with a nice summery video.

However, far more importantly then bitcoin I want to know why the hell we
don't have proof of work as an email spam filter yet!!!!!!

~~~
Lerc
Given that in the long term the cost of mining bitcoin is in the ballpark of
the electricity cost of the proof-of-work (in that being cheaper encourages
more people to mine and more expensive means mining would run a loss). You
could effectively outsource the cost of the proof of work by having bitcoin
validated email. Send a fraction of a bitcoin with an email to let it past.

If email clients maintained the wallets you wouldn't need to even worry about
the cost if you had a balance of in/out mail. You could still white list
anyone you want to email for free. A cost of $0.001 per message would have
very little impact on regular users. A botnet would still need to get the
funds somewhere to bulk send, if they cracked the mail programs internal
wallet they could drain that and send a small number of emails, but beyond
that they'd need funds, and quite frankly if they could get at the wallets
they'd just take the money direct.

It raises an interesting question. what is the value to a spammer of an
individual email? The return from advertising/scams/phishing/whatever divided
by the number of emails sent. It's got to be tiny.

~~~
pronoiac
> A cost of $0.001 per message would have very little impact on regular users.

I wonder about mailing lists - a couple of thousand members isn't too big a
list, but $1 a message adds up. Who pays it? What keeps someone from adding
fake accounts to run up the costs of lists they dislike?

~~~
Lerc
Payment isn't compulsory. You could have a number of mechanisms to clear
mailing lists, white-lists would be easiest. Since joining a mailing list
should be by user decision, provided the user interface is simple and painless
you should be able to include adding to the whitelist as part of that process.

------
sunnybythesea
Gotta love online learning...no more waiting for information to be available
in a text book and to enroll in classes to get educated.

~~~
obviouslygreen
While this is a point worth making, another is that there's also little to no
vetting or editing required to publish "information" on the web compared to
getting it into a book and into distribution.

Of course the latter isn't perfect and comes with its own evil hegemony and
other assorted issues, but the point is that there is so little barrier to
entry to posting on the web that praising speed in and of itself ignores
relevant and important issues.

~~~
doktrin
Fair point, but I would argue that "known" and trusted organizations, such as
Khan Academy or Coursera, backing a given instructor or set of materials
constitutes a form of vetting. It's not like they pick their material out of a
hat, and they're all fully aware of the potential repercussions of publishing
quackery.

~~~
PakG1
Don't forget MIT OpenCourseWare. They were first to the party. :)
<http://ocw.mit.edu>

~~~
hkmurakami
They were here for such a long time, way before anyone else and yet they are
practically forgotten now. I wish it had been given the attention it deserved
by the good folks at MIT.

------
jiggy2011
Has anybody successfully explained bitcoin to a layman?

I have a feeling this video would completely lose my mother.

~~~
fintler
I doubt it would be generally successful as a layman's explanation, but here's
my attempt.

[http://www.bringhurst.org/2013/04/03/how-does-bitcoin-
crypto...](http://www.bringhurst.org/2013/04/03/how-does-bitcoin-crypto-
work.html)

------
Iuz
Been mining for months now, did not know some of those details, great videos.

------
Siecje
Where is Sal?

~~~
ZeroCoin
He doesn't do a lot of the new videos. It's lovely to hear his voice when he
does, though. Makes you feel just a bit more special.

Perhaps Sal doesn't have a great understanding of cryptography? He doesn't do
a single cryptography video on khanacademy as far as I know.

~~~
spicyj
Sal still makes lots of videos! Lately he's been making a World War I series:

<https://www.khanacademy.org/humanities/history/euro-hist>

We just like to put up good content from other authors too when we find it. :)

