Why this exists

Investing has a lot of concepts that sound simple at first and get considerably more interesting once you look underneath them. When I run into one of those, I tend to keep pulling until it actually makes sense — what it is, why it exists, how the mechanics work, what the examples look like, where the edges are, and which of my initial assumptions were wrong.

This site more or less started in my financial planner's office. He'd explain something, I'd nod like it had landed, and somewhere between his door and my car about half of it would fall out of my head. So now I go home and write it down until it actually makes sense.

I've also discovered that understanding something today doesn't mean I'll remember the details a year from now. The general shape survives; the parts that took the longest to work out are exactly the parts that fade.

So I started building reference material for myself. Rather than leaving it scattered across notes, spreadsheets, documents and bookmarks, I'm putting it here. When I find something worth understanding, I research it and add it.

What you'll find

Each subject is written to be read two ways. Start to finish, it's a deep dive — plain language first, then a worked example, then the actual mechanics, then the math and the edge cases. Read straight down and you should be able to stop at any point and still be better off than when you started.

Read out of order, it's reference material: the definitions, the formulas, the numbers that matter, the calculators, and the mistakes that are easy to make. That's the part I'm really building this for — future me, trying to reconstruct something I already worked out once.

What it isn't

It isn't a course, a newsletter, a stock-picking service, or a curriculum. There's no plan for what comes next; I genuinely don't know what the second subject will be. It gets added when I actually research it, not before.

I'm also not presenting myself as an investment professional or claiming to have all the answers. This is an investor learning in public. Where I've simplified something or where a figure could go stale, I've tried to say so on the page.

If I got something wrong

I'd rather know. If something here is incorrect, out of date, or misleading — or if a section deserves more research than I gave it — tell me, ideally with a source. Corrections are the most useful thing anyone can send me, and fixing them in public is part of the point.

And if there's a concept you've been trying to understand yourself, suggest it. That's as good a reason as any to research something.

Everything on this site is educational and personal — not investment, tax or legal advice. The full disclaimer is here.