For better understanding the phenomena of demons, provided are a dictionary of terms often used in grimoires and demonic discussion. Also provided are a list of the 72 demons referenced in the Lesser Key of Solomon, which itself is partially derived from the The Archidoxes of Magic, The Magical Calendar, Pseudomonarchia Daemonum, Heptameron and Steganographia. Within some of these grimoires are demons not mentioned in the Lesser Key of Solomon, such as Pruflas and Lucifer. I will include these demons and indicate that they are not included in the Lesser Key of Solomon. I am using the Lesser Key of Solomon as the predominant source of this information because it is among the best-known grimoires, and provides concise and well-structured information regarding the demons it covers.