History of blockchain
The first work on a Blockchain secured by cryptographically was described in 1991 by Stuart Haber and W. Scott Stornetta ( स्टुअर्ट हैबर और डब्ल्यू स्कॉट स्टोर्नेटा ). They wanted to implement a system where documents could not be tampered with or back updated.
In 2008, made first Blockchain was done by Satoshi Nakamoto.
In 2009, That blockchain was used in the Bitcoin, which is world's first decentralize digital currency.