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System.out.println("Welcome to learncs.online!");
System.out.print("We are ");
for (int i = 0; i < 4; i++) {
System.out.print("so ");
System.out.println("excited to start your journey in computer science!");

Learn Computer Science Online

  • 61 focused lessons—from "Hello, world" to graph recursion
  • Learn Java or Kotlin
  • 900 editable and runnable code examples
  • 2,286 interactive explanations from 240 instructors, including 162 hours of live coding walkthroughs
  • 123 programming problems covering all core language features
  • 384,583 debugging challenges that train you to fix small mistakes
  • One goal: Teaching you about computer science and programming!

We'll teach you the basics of computer science and programming. Once you know these things, you can and will change the world.

Ready to go? Start here.