Every blockchain has a timestamp and every transaction has an associated timestamp. The timestamp is used to validate the authenticity of a given transaction and the exact time at which the transaction occurred. This is because the blockchain is a digital ledger that records transactions, but it doesn’t record the exact time of each transaction. This is why the timestamp, along with the time zone in which the timestamp was recorded, is of such importance.

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Let’s look at two scenarios to understand the importance of the timestamp in the blockchain.

How the Timestamp is Used to Verify Transactions

As mentioned above, each transaction on the blockchain is not associated with an exact time and date. The timestamp is used for two main purposes.

First, it is used to verify the authenticity of the transaction and the associated address. This is because the timestamp is generated by the miner that confirms the transaction. The timestamp is associated with the public key of the associated address. So, if the timestamp has a different time zone than the one associated with the address, then it could be a fake transaction.

The second purpose of the timestamp is to validate the ownership of a particular address at an exact point in time. For example, assume that you own address ‘6L5v1kXx6bzKFzJ8Y6vKvqAoAtw3qrEQK’. You can validate the ownership of this address by making a transaction with the timestamp ‘4:45 PM Today’. This means that if anyone claims ownership of this address after 4:45 PM today, then they are lying.

Note: The authenticity of a given address is validated by the private key, which is a secret number associated with the address. So, if someone copies your private key, then they can counterfeit coins associated with that address. The timestamp is used to validate the authenticity of the private key and the ownership of the address.

How the Timestamp is Used to Verify the Authenticity of a Given Address

Let’s say that we own the address ‘6L5v1kXx6bzKFzJ8Y6vKvqAoAtw3qrEQK’ and we want to prove that we owned that address at a particular time. We could use the timestamp to do so. This is because the timestamp is associated with the address and, as mentioned above, it is the public key that is validated.

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So, if we make the transaction with the timestamp ‘4:45 PM Today’, then the entire world can see that we owned address ‘6L5v1kXx6bzKFzJ8Y6vKvqAoAtw3qrEQK’ at 4:45 PM today.

Key Differences Between Timestamped and Timer-Triggered Contracts

Let’s take an example of a Timestamped Contract and a Timer-Triggered Contract. For the Timestamped Contract, the timestamp is recorded on the blockchain and the contract automatically updates to reflect the new timestamp. For the Timer-Triggered Contract, the contract triggers an event after a certain number of blocks have been validated. The Timestamped Contract always remains true to the timestamp. The Timer-Triggered Contract may also remain true to the timestamp but its validity may be compromised if there is a fork in the blockchain.