Ghost hunting is the process taken by people that believe their are spirits that, for whatever reason have not left a dwelling, place, or thing after they passed away. To do their research they use equipment like infrared recorders, EVP recorders (these are suppose to pick up the voices from the spirits), EMF meters (used to show the difference where magnetic fields are), camcorders along with some others.

I love the ghost hunting shows, but I must say in my opinion the best one out there is "Ghost Hunters", because when they do go to do an investigation they listen to the stories and try to debunk anything that could be caused by something other than a ghost. If they can't figure out where or what was causing it only then will they say it is possible it was a spirit. The video below is a perfect example of this as they explain to the man that called them that the sound a window makes blowing in the wind could also be what makes employees and others think a bucket is being dropped.

As a member of a paranormal group, ghost hunting is really misleading, granted a fun term but can be misleading. Paranormal research is more what we do is we investigate any anomaly, spirit activity, feelings, sitings. Or known haunts.
We also do background research on the history of a place and often uncover a variety of situations where the spirit would not pass on. Basically we write up everything associated with an event and include as much in the file as we can for evidence. Investigators, researchers, detectives is more what you can explain what we are and do.
As a ‘ hunter’ we try to document the place and what the problem is using, as was mentioned before an emf, evp, thermometer, standard cameras are all used to document the site or event. Many times for capturing orb, black or shadow ghosts, flicker ghosts, we can use digital. But some malevolent spirits cause since digital items to not work, because of the emp secretion.

We do more than hunt. But we are also not releasers. Those that choose to send a spirit on. We need to know why and forward that information to other professionals in the field.

IGHS, Atlanta paranormal Research Group are the best “ ghost hunters” out there and some universities have begun to explore the phenomena too. Specializing n ghost hunting.
One of the most famous was the “ entity”. A movie based on real life events.

When you look for ghosts, you're not actually trying to kill them like in deer hunting, because they are already dead

It is a bunch of people who believe in ghosts who set up cameras and infra-red equipment to capture the images of ghosts. This is usually done in old houses and castles and is always done in complete darkness. I guess ghosts don't like the daylight. Then they do a bunch of stuff like they felt a cold breeze and hype it up for the rest of us who don't believe in ghosts. Then they alway end the show with no evidence but a statement of it must have happened and they will be back.