Really? Like what, if you don't mind my asking.
I believe in ghosts. I think they are lost souls, or souls that have not yet gotten to where they need to be. I have had my own experiences.
None of our experiences have been particularly scary, except for what happened to my daughter at my parents' house, but during my daughter's adolescence we had a lot of "well, that's weird" kind of things happen. We called them "Fred experiences," having named whoever it was Fred. We would see someone walk by out of the corner of our eye and then look and no one would be there. Once my daughter knocked a bunch of plastic cups on the floor, left the room for just a moment, and when she came back they were all in a neat stack on the counter. No one else was around. She also was alone in the bathroom with the door shut, putting on her makeup, when she distinctly felt a finger run along her back where her shirt and jeans left a little gap. One more time in the bathroom she watched the medicine chest open by itself and a glass jar fall out and shatter on the counter. We don't use that cabinet except to store things, so it wasn't like someone might have left it partly open. Mostly we just had the "I know I just saw someone go back here!" experiences in the back hall of our house. And it was just me and my kids that had those experiences; my husband never did. And now that my older daughter is 23 and no longer living here, we have none of those experiences. I wondered if they would start up again now that we have another girl entering the teen years, but so far nothing.
One time when we were visiting at my parents' home, my daughter was lying on her roll-away bed which was positioned against a door that opened onto the kitchen. She was reading before going to sleep and someone started trying to push the door open, rather forcefully. I was almost asleep, but she woke me and we ran out the other door and went around to see who it was. The house was completely dark, my elderly parents and my sons had been asleep for awhile, my husband never gets up once he has gone to bed, plus the house is one of those where you can hear every footstep. No one was there.
So I do believe that there are spiritual entities that share this space with us, but I don't know what I believe about who they are and why they are here. I just read Chuck Missler's book on Aliens and his theory on there being additional dimensions we can't perceive. That's a pretty interesting read, but is it kind of out there.