I have a small one in my handbag and have had one for 30 or so years. They are kept in a cupboard at home and come in very useful for checking when things happened.
Thoughts and feelings are not recorded in them so I wouldn't really care if anyone read them although I would expect someone to ask first - if I was still alive!
What were the first ever records that you bought and when?
Parents-in-Law. What do/did you call them?