Gematria it 's a Hebrew word, and it means assigning a numerical value to a name, that may be a word or a phrase, based on its letters. People believe that with these numerical values they may understand more about the subject. It may be used for many many purposes and used so in Hebrew and Arabic magick. You may take a psalm or a demon name as you like and find its value via gematria and you may create a talisman with the same value based on planetary energies and relate these two to each other, just an example, like so; there is much more use of it.
PS : ( However, do not count on it unless you have a very reliable source or you really do know Arabic or Hebrew - not just alphabets) , because unfortunately religious fanatics as they have poisoned or aim to poison occult in many ways, here too they really fucked it up so as to relate anything to Satan from cellphones to the computer from love to games. This has nothing do with Gematria but it 's gematfuckinria _ sing Hebrew alphabets mixing it with Latin alphabet or do as you like alter values - really nonsense; btw sorry for the curse word but they deserve it; as on many sources you may see its use similar to statistics, you just torture numbers and then they say anything you want. )