To me i think there are some part of the world that still don't know anything about Bitcoin, because there are people in USA, UK, Australia, Canada, China,etc. even in Nigeria there are people that don't know anything about Bitcoin, they always think that Bitcoin is a scam, but people that know about it are making thousand of Dollars,($) I think they don't know that we are in a digital world now.
I think only the old aged people aren’t aware of the Bitcoins. Anyone who follows news has definitely known about Bitcoins. They might not be using it, but yes an overall idea about Bitcoins will be definitely there inside their mind. They don’t invest in the coin due to its complexity. Moreover as these coins are not legal in many nations, hence people are afraid to invest. Other than this, I think almost all the people know about this great innovation and they are regularly investing in it.