From the page:
There's never been a better time to achieve your goals with guided learning: introducing 100% free and flexible on‑demand courses at Atlassian University.
You can get started with courses that cover the basics – key concepts, core product features, and best practices – then validate your skills with a career‑boosting credential. Or, you can take the guided route on one our learning paths, which are series of courses designed to help you achieve a particular goal.
Previously, on‑demand courses cost $39. Starting today, you can enroll in any of our flexible and focused courses – or any of the learning paths containing those courses – for free.
I didn't even understand any of the courses, what kind of people will they be useful for?