Blockchain technology

Main purpose of blockchain technology is to create a secure digital identity reference. Identity is based on possession of a combination of private and public cryptographic keys.The combination of these keys can be seen as a dexterous form of consent, creating an extremely useful digital signature.
bitcoin is secured by 3,500,000 TH/s, more than the 10,000 largest banks in the world combined. Ethereum, which is still more immature, is secured by about 12.5 TH/s, more than Google and it is only two years old and still basically in test mode.