8.1. What is a hook?

What are hooks? Aptly named, they’re pieces of code that are designed to hook into Liferay and take over certain pieces of functionality. They allow you as a developer to override parts of core Liferay with your own implementation.

Liferay Portal has had functionality like this for a long time. The Ext plugin (formerly the Ext environment) was designed for exactly the same use case: overriding and customizing Liferay itself. The first question usually asked when experienced Liferay developers are presented with hooks is, why? Why did we need another way to customize Liferay? Isn’t the Ext plugin enough? Are you purposefully trying to confuse me?!?