Maybe its an INTP thing to be scared of having people read your journal/diarie/whatever because I also have the same thing.
Its good to have it on the computer because you can write out your thoughts quicker because your typing and you dont have to worry as much about people reading it.
I'm not sure it's an INTP thing, necessarily... I think everyone has certain thoughts/emotions they don't want others to see... it's kind of like what Anling said about not wanting anyone to know you that intimately. So, like I said, I do think everyone has those private things they don't want to share; however, I also think there are certain types who are going to be more worried about this than others, and INTPs are definitely one of them.
For me, I would never show anyone my journal, unless it was a very specific entry that I wanted them to know, and it did not include anything else that was private. I might actually imagine a close friend reading some entries, just to gain a new perspective, but I would NEVER actually
show it to them. Like, I feel like I would like for someone to know me that intimately, but I know if I actually went through with it, I would seriously regret it, so I NEVER do it.
There are lots of pluses and minuses to writing on the computer versus in a notebook... I would
personally have to side with Anling here, because I also think better with pencil and paper. Also, some people may actually write faster than they type. And as to which is less likely to be read, it again depends on the situation-- I have no siblings, a bedroom which is a major fire hazard, and a loft bed with lots of little nooks and crannies. So if I kept a notebook, it would be safe to say that probably no one would ever find it, whereas both of my parents use computers a lot in their jobs, and we all share the same two computers and use them quite frequently, so... yeah. But my friend has a little sister and a clean room and has company all the time, and is the only one in his house who is not a complete "techno-tard," PLUS he has his own laptop, so he has a computer journal.
Whatever works...