An Introduction To Bitcoin Script
Bitcoin Script, often perceived as a mere backdrop to the dazzling world of Bitcoin, is in fact a pivotal component ensuring the security and efficiency of Bitcoin transaction.
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đź•’ 7:51 PM
đź“… Jun 02, 2025
✍️ By Ecojames
Bitcoin Script
Bitcoin Script is the language Bitcoin uses to do everything it can do, from sending funds from a wallet to allowing the creation of multi-user accounts.
How Bitcoin Script Works in a Transaction
Bitcoin transactions are built using two mini-scripts:
1. scriptPubKey (locking script)
Sets the conditions under which coins can be spent. It usually contains the recipient’s public key hash.
2. scriptSig (unlocking script)
Proves the sender has the right to spend the coins. It contains the signature and public key.
- The Bitcoin network runs both scripts together to verify the transaction. If the scriptSig satisfies the scriptPubKey’s rules, the transaction is approved.
Why Is Bitcoin Script Important
- Bitcoin Script is important since it's the reason Bitcoin works without needing trust in any central authority. It allows users to program rules like:
1. Multi-signature transactions (requiring more than one person to approve)
2. Time locks (you can only spend funds after a certain date)
3. Escrow-like setups for trades
It’s also lightweight and fast—helping Bitcoin remain secure and efficient.
Advantages of Bitcoin Script
1. Security-first design: By limiting features, it reduces bugs and attack risks.
2. Deterministic behavior: Everyone sees and runs the same code, with no surprises.
3. Efficient: Fast to verify and easy to implement.
4. Simple and clear: Easier to audit and understand than complex smart contracts.
Limitations of Bitcoin scripts
1. Not Turing complete :You can’t run complex programs or loops.
2. Limited flexibility
- More advanced use cases need extra layers like the Lightning Network or sidechains.
3. Only 256 opcodes
- That’s enough for basic functionality, but not for everything