Lessons, written and narrated
Every concept explained in prose you can actually read, and read aloud like a podcast for the commute, the gym or the dishes.
Median U.S. pay in computer and IT jobs: $109,470, against $50,980 across all occupations. Source: U.S. Bureau of Labor Statistics, May 2025 wages.
Full courses for cloud, data and AI certifications.
Opens in your browser. Nothing to install.
Start studyingThe web app and the Android app share one account: the lesson you were on, the questions you missed and today's review are waiting on both.
Try it: one question and one query from the SQL course, ten seconds each.
SQL Fundamentals · Question
Which query returns only the name column of the artists table?
SELECT artists FROM name;SELECT name FROM artists;FROM artists SELECT name;The column comes first and the table second, so the column goes after SELECT and the table after FROM.
Practice · SQL
Calculate the total sales amount for each region.
SELECT region, sum(amount) AS total
FROM sales
GROUP BY region
ORDER BY region;
Not that one. Try another chip.
| region | total |
|---|---|
| iberia | 130 |
| nordic | 90 |
The whole course: lessons, questions and exercises. Nothing to install.
Continue in the app, with the same account.
























Six ways into the same course, all in one app, because reading something once isn't the same as knowing it.
Every concept explained in prose you can actually read, and read aloud like a podcast for the commute, the gym or the dishes.
Stuck at 11pm? Ask. It knows the concept you're on and answers within your course, not in general.
Practice per concept, then full mock exams, weighted by domain like the real thing.
Hands-on SQL, Python and DAX tasks on a real dataset: complete the code and check it on the spot.
What you got wrong comes back exactly when you're about to forget it, not before.
Fast rounds that turn revision into something you'd actually open on a Tuesday night.
Courses developed by tech professionals with years of experience, and anchored to the vendor's own documentation.
20 courses · 749 lessons · 7,490 practice questions
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Cloud, data and AI skills are some of the best paid in the job market, and employers keep hiring for them.
Approximate yearly average, 2025–35. Source: U.S. Bureau of Labor Statistics, 2025–35 projections.
2025–35, much faster than average. Source: U.S. Bureau of Labor Statistics, 2025–35 projections.
U.S. starting salaries, mid to high experience band. Source: Robert Half 2026 Salary Guide, 2026 edition.
U.S. starting salaries, mid to high experience band. Source: Robert Half 2026 Salary Guide, 2026 edition.
U.S. starting salaries, mid to high experience band. Source: Robert Half 2026 Salary Guide, 2026 edition.
Lessons you can read, audio you can listen to on the way to work, and practice that remembers what you got wrong.
Opens in your browser. Nothing to install.
Start studying“This app is the ‘One Lake’ for preparing the certification exams. Really worth it.”