Ask HN: Is it okay to copy someone else's idea?

Sometimes I see a Show HN or product launch and think "wow, I'd love to do something like that", perhaps as simple as changing the target customer.

Is it okay, for example, to take an idea aimed at developers and build something almost identical, but selling to designers? If it's pretty obvious the author of the original idea plans to expand in that direction, am I crossing the line by jumping ahead and trying to get there first?

Google did it. Facebook did it. Then again, don't do a Facebook for dogs. Or dog-owners.

Of course that's ok.

Nothing is ever entirely new. Everything has parts of other things in it.

Copying was and is one of the most fundamental processes in human culture. You have learned to speak by copying! The "intellectual property" propaganda is a relatively new and artificial construct.

akulbe has hit a couple of important points. Just because someone thought of something, or even made a thing, doesn't mean they own the idea. If you copy their exact execution, shame on you. Otherwise, go for it. On paper, any social network is the same thing. But we don't use friendster anymore.

IF it seems appropriate to give credit to someone else for inspiration, go for it.

Just remember, the market will determine the winner. Effectively, that's really all that matters.