Thsiquestion is wonderful but I feel it could take a while to answer it. As different people believe different things. In my single and personal belief the spirit of anything can cause harm by our intent if our words are knives and scare us over the ages like the time mother nature has done for the grand canyons the same is for the human spirit. The Human spirit is strong but fragile and how we look and take care of our own and others can extend to deeper meaning in life.
I do hope this helps and I look forward to other views on this topic.
It mostly depends on the type of spirit and it's personality. Human spirits that haunt places are mostly just noise makers, or cabinet-openers. Some ones, however, that were murdered or died unrightfully, can be malevolent and throw things, which could result in injury. You could also wake up with strange bruises or cuts on your limbs. Any spirit can be malevolent and cause ill things to happen, however some spirits are stronger than others, which could result in more drastic things.
A typical hauntingof a human spirit or spiritsincludes things such as seeing apparitions;cabinets or doors opening and closing by themselves;noises such as voices, laughs, screams, etc; or even sometimes being touched by the spirit. Mostly non-violent and non-harmful. However, spirits can also induce nightmares to some people if they don't like them.