Pick a course, finish the program.
Each level is real, runnable code with a few pieces missing. Choose the correct piece for every blank, run it, and see the actual output.
JavaScript
Master JavaScript from the ground up. This comprehensive course covers everything from variables, data types, operators, conditions, loops, functions, arrays, and objects to advanced concepts such as DOM manipulation, events, asynchronous JavaScript, APIs, promises, async/await, and modern ES6+ features.
Start PlayingTypeScript
Master TypeScript from the ground up. This comprehensive course covers the type system, interfaces, unions, functions, classes, generics, enums, and type narrowing — the exact skills used to build production React, Angular, and Node.js applications — through 12 hands-on lessons.
Start PlayingPython Programming
Master Python from the ground up. This comprehensive guide covers syntax, data structures, functions, object-oriented programming, iterators, decorators, modules, and file handling through 58 hands-on lessons.
Start PlayingLua
Master Lua from the ground up. This course covers tables, Lua's single all-purpose data structure, closures and scope, metatables and metamethods, string pattern matching, and how Lua gets embedded into games and applications, through 12 hands-on lessons.
Start PlayingPHP Programming
Master PHP from the ground up. This comprehensive guide covers syntax, forms, sessions, object-oriented programming, MySQL integration, authentication, and modern tooling through 70 hands-on lessons.
Start PlayingRuby
Master Ruby from the ground up. This course covers Ruby's "everything is an object" philosophy, blocks, procs and lambdas, classes and modules, collections, and the Gems/Bundler ecosystem behind Ruby on Rails, through 12 hands-on lessons.
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