Well, I started journaling in paper journals when I was a kid, and did that for many years. I stopped journaling when I injured my arms with tendinitis, and I've never really gotten back into paper journaling since then, because it tends to still hurt my wrists if I scribble with a pen anywhere near as fast as I think.
So I started keeping an online journal as a part of my website, and did that for a while, and liked it. But I tended to treat my journal entries as essays, rather than just scribbles, as I would normally write in a private paper journal.
I first joined LiveJournal because I knew some people here in the Buffy fandom and I wanted to be part of their community. But I quickly began to find other things I liked about being here (and mostly abandoned the Buffy fandom).
- I can keep a journal that is as formal or as informal as I like. Sometimes I write entries that are similar to essays; other times I write chaotic stream-of-consciousness. Sometimes long entries, sometimes brief. For some reason, I didn't feel so free to do this when I had a separate online journal at my website. Possibly because I had to create a separate page for each entry, whereas here it's all done automatically. So, at LiveJournal, I journal much more like my paper journals, which I like.
- I find that the community aspect encourages me to write more often than I might otherwise. People want to hear from me, even if it's just random rambling.
- I tend to write whatever I'm thinking or feeling, more so than I would actually tell people face-to-face, because it's just me journaling. But in this particular milieu, people can respond to what I've written, and so I get a sounding board. Thoughts that once would have been private here receive feedback. People tell me when I'm full of shit or blowing something out of proportion. I appreciate that and it has sometimes helped me to see something in my life differently than I ever had in the past.
- I have control over who can read each individual entry, which encourages me to write without censoring myself. I just write whatever I'm thinking, and then can consider afterward (before I post) whether I'm comfortable making it entirely public. Most of my posts *are* entirely public, but having that ability makes me more comfortable writing completely honestly.
Those are the main things that pop into my mind. I've found my LiveJournal much more fulfilling than my other forms of journaling, but that's just me.