Blockchain is an open and distributed ledger with continuously growing list of records (blocks). Blocks are linked in secured manner using cryptographic techniques.
A Block contains;
a. Index
b. Previous block’s hash
c. Timestamp
d. Data (Transaction – related to Cryptocurrency)
e. Digital Signatures
f. Nonce (Proof of work )
g. Hash
Advantages
a. Double spending proof
b. Decentralized System
c. Peer-to-peer network
d. Low or No Transaction Fees
e. High security (cryptographic techniques)
f. Maintain anonymity
Disadvantages
a. Need high computational power (not for normal users)
b. Power consumption
c. Updating the system is very difficult