One site for the 14 most popular languages. Pick a track or a language — run code instantly, no setup.
Python runs real Python (Pyodide, no terminal needed). JavaScript runs live too. Other languages show simulated output — install locally for real run.
Pick once — we adapt every explanation to your level. Short, hierarchical, not long paragraphs. You can change anytime by clicking the badge top-right.
Levels: Grade 1-5 → 6-8 → 9-12 → University/College → Pro. Same code, different depth.