I've been trying to journal in one form or another for as long as I can remember. Naturally, I went through many systems during those years. Here's a few of those.
The simplest solution of all - plain paper and pencil. I tend to come back to it once in a few years, with some new ideas, but it never sticks. Too bad, because I really love the idea of having one central journal in my life, which does not require a battery or internet connection to be with me everywhere I go. There's also something to be said about tactile feedback you get from paper. I've tried many things from basic to-do lists, kanban boards, work journals, diaries, bullet journaling and many things in between, but it never sticks.
Part of the problem is that many of my notes are related to programming or other technical aspects, which benefit greatly from ability to copy-paste reference materials. Another problem is my approach. I heavily edit my notes, but on paper you cannot go back to the previous paragraph and add a new sentence, or move it from the end to the beginning. I still try, and it quickly ends up looking nasty.
Now that paper is out of the question, we get to the digital alternatives.
First it was one big text file - life was simpler back then. Each new note would go to the top of the file, since recent notes are used more frequently. When the file got too big, I created new ones for different topics. And that was fine for a while.
While this is a great and future-proof approach for some, it still has significant drawbacks. First of all there's lack of basic formatting, which gets annoying when there's a wall of text. I could live with that though. Bigger drawback to me was lack of multimedia - I cannot simply add a screenshot or some picture to a text file to illustrate my text. Text files are also a pain to sync to your smartphone without using any specific note-taking app.
Next was Evernote. It was fine for a few years, but I never felt like paying for it back then, and limitations to free accounts were annoying. After a push to convert to paid subscription I moved out of it.
I used it as a basic personal KanBan board. It was very satisfying to move notes around different columns. The problem was that when they were archived, they were never to be seen again, which is fine for projects and todos, but not for journaling.
At first was refreshing to have a bunch of digital post-it notes instead of my heavily structured EverNote hierarchy. When migrating out of it I realized that it came at the price - losing structure means losing meta-information and now everything is harder to discover and review. I tried using tags, but they were not very friendly. Google Keep was a very primitive tool for occational note-taker, but definitely not a journal. That was my mistake, as it never positioned itself as such.
Next came plain text files again! But now with a bunch of bash scripts and enforced timeline through file names and folders. That was fine for a while.
That was the last move. It's always a bit strange when default apps fit your requirements perfectly, but in this case it does: