Bitcoin is a digital currency that was created by Satoshi Nakamoto in 2009.It is created electronically and impossible to control it.This currency are not printed currency like dollars or euros.Running computer all around the world are producing it.Owing to this reason they are different from other currencies.
The main reason why bitcoin is unique from other currencies because its value is continuing to rise up. Its demand is continuing to grow more because many people are keep buying bitcoins.
But it's very unstable thing unlike real estate or smth. The demand is not grow nowadays.