automation
What is API (Application Programming Interface)?
A set of rules that allows different software applications to communicate with each other and share data.
In plain English
An API is the plumbing that connects software. When Zapier connects your QuickBooks to your Mailchimp, it's using both products' APIs. SMB owners don't need to write APIs, but understanding they exist helps demystify how automation tools work — and why some tools integrate easily (good APIs) while others don't (no API or poor documentation). Most modern SMB software has an API, which is why the automation possibilities are virtually unlimited.