Jed McCaleb is the CTO of the Stellar network. He states that Stellar was inspired by Bitcoin and in a lot of ways is complementary to it.
McCaleb notes that Bitcoin is focused more on the currency aspect of things, whereas Stellar is focused on how to make a common language between different financial institutions and currencies.
It would make Bitcoin interoperable with dollars or Euros or Pesos and many others and all these currencies can be easily traded with each other.
In other words, Stellar is a blockchain that enables users to send money to anyone in the world, for fractions of a penny, instantly, and in any currency.