Bitcoin are one of the originals. We also have other cryptocurrencies that has proved to be the best as well in terms of security and value and that is Ethereum. Let me add that the Propthereum ICO crowdsale will run off a decentralized Smart Contract that runs on the Ethereum Blockchain. It is secured with a 256-bit encryption which makes it secure and reliable. Propthereum Tokens will be minted as PTCs. These coins are a digital representation tracking the funding of our ICO and crowdsale. The pre-ICO token sale will take place on November 10, 2017 at 12PM GMT. You may check this link for more information: www.propthereum.io