Obsidian is a note-taking and knowledge management app. What I like about it is that it saves all of your notes in markdown files in a local folder.
It is a free tool and because it stores the data locally in plain text files, you do not rely on a cloud-service or on keep using Obsidian for the rest of your working life. You can easily migrate your notes from these simple markdown files to something else if you prefer and they do not get lost or locked behind a paywall if the service stops working.
I use it as a repository for notes, ideas, code snippets, and lists, but there are many different ways of using it. One strength of Obsidian is the many community-driven plug-ins that adds amazing functionalities and customizations so you can design the workflow that suits you the best.
The freedom of Obsidian is one of the things I really appreciate about it. I have one single Obsidian workspace or so-called Obsidian Vault. Some people like to have multiple for different projects or for a separation between personal/work notes. I just like my single everything-goes-here system.
You can easily change how Obsidian looks and behaves via the plug-ins. Currently, I am loving the Yin Yang theme in light-mode(!) with an accent colour in a slightly darker purple (#DAAFFF) than default.
I don’t keep a strict structure to my Obsidian Vault. Whenever I feel like writing something down, I just open a new note and start writing.
Currently I do have a vague structure
daily contains my daily notes in Obsidian. If you look up almost any guide on how to use Obsidian, daily notes are usually an essential part. It can be a journey entry, a daily to-do list or whatever you prefer. My current template for daily notes is this template from Dann Berg.Academia contains meta-level notes about my work. Here I can find the text snippets with the standard formatting of my affiliations and acknowledgement that I need to put into every paper I write along with some general notes on workflow.Personal contains notes for my personal life. Right now this contains an unfinished list of all my subscription software and apps so I know what to keep and what to cancel.Reading contains notes for research papers I have read and that is linked to my Zotero.Students contains a note for each student I supervise or co-supervise. This contains when they have to hand-in, outlines of their projects and meeting notes and agreements.templates contains all my Obsidian templates and is rarely opened from within Obsidian. However, it is nice to access them easily and to have them in the same git repository as the rest.