A method to organize knowledge in the way we think: as an entangled web of information.
A Zettelkasten enables you to to organize your notes into an entangled web of information. This in turn allows you to discover new ideas and connections between your notes which otherwise would have been kept hidden.
The bigger your Zettelkasten grows, the valuable it gets: Imagine a Zettelkasten which contains thousands and thousands of ideas. If you now have a specific question and start to explore this Zettelkasten it will provide ideas which you've already forgotten a long time ago - thus it will probably answer your question in surprising ways.
To make the most of a Zettelkasten, you should follow these 12 principles:
Each note should contain one idea and one idea only.
Each note should be self-contained and comprehensible on its own.
Whenever you add a note, make sure to link it to already existing notes.
Whenever you are connecting two notes, make sure to briefly explain why you are linking them.
Use your own words to express an idea, so your future me is able to understand it - even years later.
Add the reference to the original source to your note.
If you have thoughts of your own, add them as notes.
Don't waste time thinking about a neat folder structure or preconceived categories.
When you start seeing connections among notes, create "connection notes". Their purpose is to link together other notes and explain their relationship.
An outline note is a note that simply contains a sequence of links to other notes, putting those other notes into a particular order to create a story, narrative, or argument.
Instead, link to new notes that explain what’s wrong with the old ones.
You can never have too much information in your Zettelkasten.