RESIDUAL- An imprint left in this plane of existence. Like rewinding a movie and watching the same scene over and over again. Could be something you see, smell or hear. This is a Non-intelligent haunting.
INTELLIGENT- A haunting in which the spirit communicates by sound, sight or smell with an intelligent response to questions when asked.
POLTERGEIST- A haunting in which objects are moved. Anything from a dime being moved a little to picturesflying off the wall.
DEMONIC- Classified as a haunting in which the spirit is physically hurting the occupant(s). These are not at all common.
Other types of entities that may be encountered:
Aliens-intra/extraterrestials, interdimensional beings, possible time-travelers, residuals of living people, psychic entities, created thought-forms, elemental beings, astral entities, shadow entities, and others not named.
Digital Voice Recorder - A device which is used to capture evp's, in hopes to help prove the existence of life after death.
Electromagnetic Field Reader - A device that reads frequency selective measurements in which the measurement system consist of a field antenna and a frequency selective receiver or spectrum analyzer allowing to monitor the frequency range of interest...Wikipedia It is believed that spirits are made up of electromagnetic fields and therefor can be detected through these devices.
Digital video reorder - This is a four camera system that records video or video and audio. We use a four camera night vision set up. These are normally stationary cameras.
Video camera - We utilize a few of these cameras. These are our video/audio cameras. We normally carry these around with us to document any paranormal events.
Infrared thermometer - A thermometer which infers temperature from a portion of the thermal radiation sometimes called blackbody radiation emitted by the object being measured...Wikipedia We utilize two different kinds of infrared thermometers. One as described above and the other that reads actual room temperature.
K2 Meter - A type of EMF meter which reads not only EMF readings but different types of radial frequencies as well.
Ovilus - An electronic speech-synthesis device which utters words depending on environmental readings, including electromagnetic waves...Wikipedia
Ghost box - A scanning radio receiver that cycles through the radio spectrum picking up snatches of broadcast signals and static...stack exchange