So, this decimal point...

Let's get on to the decimal. We have a category, say 22 Contracts, and we want to store some things there.

We create a Johnny.Decimal number by adding a decimal point to our category, and starting at number 01 . We start at .01 and not just .1 because of the way that computers sort files. Also it's more consistent, and consistency is elegant. So, let's do that.


I was kinda nervous but that turned out to be really easy. Now we just decide what we're keeping there and give it a nice name.

22.01 Cleaning contract

Now, we need to store another contract. What to do? Well, just use the next number.

22.02 Office lease

You create a full Johnny.Decimal number by choosing a category and looking for the next available number after the decimal. The thing to remember here is that the number after the decimal has no meaning whatsoever: we just start at .01 and work our way up.

"What happens when I get to .99", you're wondering. You never will. And if you do, the category you defined was almost certainly too broad. Split it up.

Give your Johnny.Decimal items simple names

This system allows us to give concise names to things, because we already know from the number which category they're in. I created 22.01 Cleaning contract because it just reads better that way, and it's still pretty short, but you could have gone with 22.01 Cleaning if you'd preferred. You're already in a folder called Contracts. Everything that starts with 22 is a contract.

Let's store a file!

We’ve created areas containing categories and in those categories we have Johnny.Decimal numbers. We're now ready to hold our actual things.

This is where your stuff lives. This is where you keep your spreadsheets and your Word documents and your scanned receipts and your notes and references and emails and whatever else it is that you are keeping in your system.

It'll look like this.

Concepts - After the decimal - Files in 22.02 highlighted green.png

What not to do, ever, for any reason, on pain of death

A note to those of you who aren’t very computer-y. We have the concept of “trees” in computerspeak. It’s an elegant one: you have a tree, which has multiple branches, and at the end of the branches are leaves.

In our example, the tree is your Johnny.Decimal system. It has up to ten branches, which are your areas; each of those has up to ten branches which are your categories. At the end of those branches are leaves, and that’s where you store stuff. I’ll be using this language here, so it’s good to understand. It’s also just a nice analogy.

Now, a very important note: you may not store things anywhere other than in a folder with a full Johnny.Decimal number. In computerspeak, you can’t store things “further up the tree”. That means you’re not allowed to do this.

Concepts - After the decimal - File in a branch.png

Instead, find the right home for that document. It must relate to something! Find what category that something is, and if it doesn't exist, create it. Then create a new Johnny.Decimal number inside that category, and store your document there.

The system does have a way of handling data that is about the area or category itself, but if I tell you about it now your head will hurt. It's covered later.