This is a starter video note. Copy it, or delete it once you add your own.

Use note_type = "video" and put the YouTube URL in source so the video embeds at the top. Headings like 12:40 make timestamped notes easy to scan.

Takeaways

• The browser event loop is a queue: JavaScript runs one thing at a time, then picks the next callback.
• Rendering and I/O are not the same queue as your JS callbacks.
• setTimeout(fn, 0) does not run immediately; it waits until the current stack is clear.

Notes

01:15 — Call stack

JS is single-threaded. Each function call is pushed onto the stack and popped when it returns.

This is a starter book note. Copy it, or delete it once you add your own.

Use note_type = "book", creator for the author, and one heading per chapter. Set status to in-progress while you are still reading.

Takeaways

• Reliability, scalability, and maintainability are the three reasons we bother with data systems.
• There is no single storage engine that is best for every access pattern.
• Replication and partitioning are separate problems; most systems need both.

Chapter 1 — Reliable, Scalable, and Maintainable Applications

Reliability means the system keeps working when things go wrong, not only in the happy path.