The library

Start with one of ours.

Each of these is mapped claim by claim, so a good place to feel how a debrief works. Or skip the list and bring your own.

• intermediate

  Database indexes

  Explain what a database index is, why it speeds up reads, and what it costs.

  Start
• foundations

  Compound interest

  Explain what compound interest really is, why when you add money matters as much as the rate, and why small rate differences grow into large gaps over time.

  Start
• foundations

  How vaccines work

  Explain what a vaccine actually shows the immune system, what it leaves behind, and why the next real exposure goes differently.

  Start
• foundations

  Supply and demand

  Explain why a market price settles where it does, what happens when it's off that point, and the difference between a shift in demand and a movement along the curve.

  Start
• foundations

  Closures

  Explain what a closure retains, when that access is used, and how changing the surrounding variable affects the result.

  Start
• intermediate

  Async & await

  Explain what await actually does, why it doesn't freeze the program, and the order things run in.

  Start