Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

package-private

The access a member gets with no modifier, usable by any class in the same package.

A member declared without an access modifier is accessible from code in the same package only.