Getting Started Guide - a good place to start if you are new to ZAP
Desktop User Guide - the help included with the ZAP desktop application
API Details - a comprehensive guide to the ZAP API
Alert Details - detailed information on the alerts ZAP can raise
Docker Details - detailed information on ZAP's docker images
FAQ - Frequently Asked Questions
ZAPping the OWASP Top 10 - a guide mapping Top 10 items to ZAP functionality that can assist IT security personnel