Layer 3

App-specific chains on L2.

Educational content only. This page does not provide investment, legal, or regulatory advice.

Why it matters

Layer 3 matters because it affects financial interpretation, product decisions, and industry communication.

Layer 3 is commonly explained through its core definition and the practical example used in the glossary.

A common mistake is to use Layer 3 without understanding its operational and regulatory context.

Layer 3 may vary across payment rails, regulations, and market practices.

3D Secure

Security protocol for online cards.

Account Abstraction

Smart contracts as wallets.

Account Updater

A service that refreshes expired or reissued card details for recurring billing merchants.

Simulation of human intelligence by machines.

Algorithmic Trading

Trading using automated algorithms.

API

Application Programming Interface.

Google Search Central

Google Search Central: Helpful, reliable, people-first content

Defines trust, helpfulness, and people-first expectations for YMYL-adjacent content.

Google Search Central

Google Search Central: Title links best practices

Supports title hygiene and metadata governance.

Coinbase

Coinbase Learn: Crypto glossary

Reference source for crypto infrastructure terminology.

Author

Founder and multilingual fintech glossary editor

Reviewer

Editorial and source review layer

Reviewed

3/15/2026