A time ago, I commented a discussion here on dev.to titled How do you make notes? Here it is long my reply.
I love plain text. It's future-proof. You can use any text editor. Notepad++, SublimeText, Vim, Visual Studio Code, you name it. I use plain text for almost everything.
I write all my notes using Markdown. It's formatted plain text that can be converted to HTML. Markdown is already on README files in GitHub and almost everywhere around the Internet.
To write and organize my notes I use Notable.
For my task list, I have a todo.txt file. One task per line. Each task has a priority, due date and optional tags. For ideas and tasks in the future, I have a later.txt. Once a task is done, I move it to a done.txt. I keep it as a brag document. For more ideas to use plain text, you can read Lifehacker Ten clever uses for plain text.
I have a note for every blog post, podcast, video and book I found interesting. I group these notes using the tag: "til", short for "Today I learned". I write the date, the source, the keypoints and my reaction.
I capture ideas and thoughts on my phone. "Always have something to keep notes" suggests Pragmatic Thinking and Learning
Recently I found a note-taking system: Zettelkasten. In short, write on your own words what you learn on a piece of paper or card, put an index number and connect it to your existing notes. Although there are editors for Zettelkasten, I have my own slipbox and I keep my cards with pen and paper.
To read more about the Zettelkasten method, check my takeaways from the book How to Take Smart Notes.
Happy note taking!