Why should you care?

Some problems (trees, nested JSON) are simpler to express recursively than with loops.

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function factorial(n) {
  if (n <= 1) return 1;
  return n * factorial(n - 1);
}
console.log(factorial(5));

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What happened?

• factorial(5) calls factorial(4) … until n <= 1 returns 1.
• Results multiply on the way back up.

Practice next

1. Run factorial(5) and trace on paper.
2. Try factorial without base case and read stack overflow.
3. Rewrite factorial with a for loop.
4. Write recursive fibonacci(6) and compare speed to iterative version.
5. Add a depth limit parameter that stops recursion early.

Remember

Function calls itself Must have a base case Watch call stack depth

ScriptVerse org chart

A CRM renders nested departments by recursively walking a tree of { name, children } nodes.

Outcome: Recursive tree walks match nested JSON from org APIs naturally.