> ## Documentation Index
> Fetch the complete documentation index at: https://docs.theblockchainlibrary.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Double Spend

> An attempt to spend the same digital asset more than once.

# Double Spend

An attempt to spend the same digital asset more than once.

## Definition

An attempt to spend the same digital asset more than once.

## Why it matters

Security concepts help users and developers recognize common blockchain attack surfaces and defenses.

## How it works

The network maintains a timestamped transaction history. When a user tries to spend a token, nodes check the ledger to ensure the input hasn't been used in a previous, confirmed transaction. Only confirmed transactions are accepted into a block.

## Real-world example

Proof of Work mining ensures the order of transactions, making it impossible to rewrite the chain to spend the same coins twice.

## Advantages

* Ensures economic scarcity
* Provides trust in digital transactions
* Prevents fraudulent asset duplication

## Limitations

* Mitigation requires network latency
* Requires constant computational oversight
* Potential risk during 51% attacks

## Common misconceptions

* Double spending is often thought to be common in crypto, but it is effectively impossible on secure networks like Bitcoin. People also confuse it with transaction delays.

## Related knowledge

* [Phishing](/generated/v2/glossary/phishing) — term
* [Smart Contract Audit](/generated/v2/glossary/smart-contract-audit) — term
* [Sybil Attack](/generated/v2/glossary/sybil-attack) — term

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**Canonical knowledge ID:** `glossary:double-spend`