Think of an API as a friendly middleman that makes sure your software can politely ask another service for data or perform tasks. In the Bitcoin world, APIs help developers connect wallets, exchanges, or monitoring tools to the network. For instance, Bitcoin Core’s RPC interface lets you query the blockchain, broadcast transactions, and gather node stats.

APIs also power various third-party services that simplify complex Bitcoin operations, like generating addresses or analyzing transaction data. They enable developers to build new apps without reinventing the wheel. This fosters innovation and helps the entire ecosystem evolve, even if sometimes you have to read a bit of technical documentation to figure out which function does what.