# Graders, data access and licences

Lesson 2 of [AI benchmark foundations for buyers](https://aibenchmarkindex.com/academy/ai-benchmark-foundations.md), 14 minutes.

The grader and the data are as important as the tasks. A good task with a weak grader gives a weak score. Grader types Each listing on this site records one grader type. - exact: the output must match a reference answer. It is cheap and repeatable. It can reject a valid answer in a different form. -…

The rest of this lesson is for learners enrolled in the course. [See how AI benchmark foundations for buyers works](https://aibenchmarkindex.com/academy/ai-benchmark-foundations.md).

Also on the [web page](https://aibenchmarkindex.com/academy/ai-benchmark-foundations/graders-data-access-and-licences).