Blockchain 101: All you need to get started with your crypto journey

What is the need for blockchain technology?

How is blockchain secure and immutable?

Structure: Every block in a blockchain contains the following details

  1. Index: The position of the block in the blockchain
  2. Previous hash: This contains the cryptographic hash of the previous block in the blockchain
  3. TimeStamp: This contains the timestamp of when the block was added to the chain
  4. Hash: The cryptographic hash of the current transaction
  5. Data: The actual data stored on the block (Note that this data is public)
  6. Nonce: How many iterations occurred before finding a valid block (More on this later)

How does a transaction occur?:

  1. Every blockchain starts with the genesis block. This is the beginning of the blockchain and contains the basic details. The previous hash and index of this block will be 0.
  2. Now we know that, when a new block is added, the following data is added: index, previous hash, timestamp, data, hash and nonce. Except for the hash and the nonce, the rest of the data is fixed. Let us see how these values are calculated.

Calculation of hash:

How does this make blockchain immutable?

  1. Block A has the previous hash 0, a nonce and a unique hash having four 0s
  2. Block B has previous hash equal to block A's hash, Block B has its own hash generated using the previous hash (block A's hash) and unique nonce.
  3. Block C has previous hash equal to block B's hash, Block C also has its own hash generated using the previous hash (block B's hash) and unique nonce.
  1. The hash in block A becomes invalid for the given nonce because the data changed.
  2. The hash in block B also becomes invalid because its previous hash (block A’s hash) changed.
  3. The hash in block C also becomes invalid and so on.

Types of blockchain

  1. Public blockchain: The ledger is not owned by anyone. There is no consent required to mine the blocks. Anyone in the world can participate and maintain the blockchain.
  2. Private blockchain: Only the trusted parties can take part in the transactions occurring in the blockchain.

What does native currency mean?

What are Smart Contracts?

What is tokenization?



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