What is the difference of running a bitcoin app to, say, a forex site in terms of security? It depends on what you mean by "forex site". If you mean "a bucket

What is the difference of running a bitcoin app to, say, a forex site in terms of security? It depends on what you mean by "forex site". If you mean "a bucket shop, which uses as its source of random numbers currency fluctuations", then a forex site is approximately as risky as a bitcoin exchange, modulo the fact that the forex frontend almost certainly has no lever on it which will actually cause outgoing wires and the bitcoin exchange almost certainly does. That's actually a pretty big modulo, come to think of it. [Edit to add: This is just talking about software security. Bitcoin exchanges have a legal security problem which forex sites don't, because you can use Bitcoin exchanges to move money and you can't conveniently do that with forex sites.] If by "forex site" you mean e.g. a bank's foreign currency trading desk, you're asking me to compare the US Army and the Boy Scouts in terms of potential to conquer arbitrary nations. what do you mean with major result in cryptography? SHA-256 has some time complexity associated with it. A major result in cryptography gives some variant of attack against it with radically lower time complexity than we currently think attacking it requires: say, it allows a speedup of 2X, 4X, etc etc. (It is unlikely, but conceivable, that it would go to O(1) all at once.) This is like every other cryptographic algorithm. Producing major cryptographic results is hard. Weaponizing them is harder, still: 2X improvement probably doesn't make any attacks practical which weren't practical before, it just posts a "Warning: this algorithm will die in the foreseeable future, transition off at the earliest convenience" notice to all interested parties. But, again, Bitcoin advocates love wrapping themselves up in crypto because it makes them feel secure. Crypto is one teeny tiny little bit of their systemic security. It isn't the important bit. That's a very impressive looking deadbolt you have, there, and defeating it would probably be pretty difficult, but the pane of unreinforced glass right next to it looks a little promising and, if you check with your 17-year old architect who is doing this in his spare time, he might be able to confirm that your house only has two walls and no ceiling.