Well, the original one isn't unordered, and isn't meant fundamentally to be "searchable" (its original "implementation" being index cards).
Here's my attempt at conciseness:
A zettelkasten is like a bunch of files in a single folder with
1. a naming schema that kinda indicates what follows what (an ordering scheme, but persnickety and optional, see https://zettelkasten.de/posts/luhmann-folgezettel-truth/), and
2. links in between the files, originally just by writing the names to be manually looked for.
Some people use 2 to be able to get rid of 1, as with an indication of PREVIOUS (link) and NEXT (link)
The point is that you have one thing on each card / file that you might want to go back to on its own.
It makes a lot of sense in academia where you want to be able to trace ideas in a referenceable way, identify your own takes on bits of other people's work, and connect different sources together when you see similarities.
Here's my attempt at conciseness: A zettelkasten is like a bunch of files in a single folder with 1. a naming schema that kinda indicates what follows what (an ordering scheme, but persnickety and optional, see https://zettelkasten.de/posts/luhmann-folgezettel-truth/), and 2. links in between the files, originally just by writing the names to be manually looked for.
Some people use 2 to be able to get rid of 1, as with an indication of PREVIOUS (link) and NEXT (link)
The point is that you have one thing on each card / file that you might want to go back to on its own.
It makes a lot of sense in academia where you want to be able to trace ideas in a referenceable way, identify your own takes on bits of other people's work, and connect different sources together when you see similarities.