How the cards are made
Written to a public standard, checked against official sources, dated, and open to corrections.
Starts from zero, goes to advanced
Every topic opens with a level that assumes nothing, explains each word before it is used, and climbs to what a senior engineer or a compliance lead would ask.
Checked against official sources
Each topic lists the official documentation, standards or statutes its cards were checked against. We do not copy other courses or tutorials.
Dated and versioned
Each topic shows when it was last reviewed and which versions it covers, so you know how current it is. Fast-moving details are named with their version.
Honest about limits
Law and compliance topics are study aids, not legal advice; check the official text before you act. Where a rule was not final when we checked, the card says so.
Certificates that can be checked
The final test is scored on our server, never in your browser. At 80% or more you get a certificate with a public check page, so an employer or teacher can confirm it in seconds.
Corrections welcome
Spotted a mistake or something out of date? Use Report a problem on any topic. We fix it, review the topic again and update its reviewed date.
Made for
- Students
- Short daily cards and a test before exams.
- Job seekers
- Interview-level questions and a certificate for your profile.
- Working developers
- Cheatsheets, pitfalls and what changed in the latest versions.
- Career switchers
- Learning paths that order the topics for one goal.
- Everyone else
- Start from zero levels in plain words, with everyday comparisons.
- Employers and teachers
- Open the check link on a certificate to see that it is real.
All learning is free and runs in your browser. Progress stays on your device, or with your account when you sign in. See the privacy page for what a certificate record keeps. Start learning