Another tool in the ghost hunter’s arsenal.
The primary use of a digital voice recorder is to catch EVP's, electronic voice phenomena.
The idea is someone calls out, or asks a series of questions while the device is recording.
The recording is then reviewed to see if there is an extra voice present, giving a response to the human half of the conversation.
A couple of things to be warry of though. If the device is recording in low quality setting and moved around while recording, you can get false responses.
There are a few examples of where the response is a perfectly ordinary noise that has been recorded in poor quality and misheard.
An example of this could be clothing rubbing very near the microphone.
Used well, they are a great tool and recordings can be very compelling.
The recordings can also be used for debunking, catching human acts that are misinterpreted.
Also if the time stamp is correctly, can be used to cross reference other recorded phenomena.