Graphology is the study of handwriting. It looks at patterns and characteristics of the writing, to make inferences of a person's character.
Graphology has been used as a tool historically. Julius Caesar saw the value in it. There is debate about whether it is scientifically valid or whether it is a pseudoscience. The limitations are that people write in different ways, in different circumstances. Different writing styles are taught at different schools and countries.
I have read that it was used in parts of Europe for shortlisting job applicants. That is, establishing whether applicants were of good, trustworthy character or not. When I was involved in recruiting staff, I asked applicants to write their referee details. That was merely to check that their writing was legible and to check their attention to detail ie. correct phone number and workplace. I would be concerned about discriminating an applicant making any inferences from graphology.
Graphology considers the structure of the page, the margins and the size, weight, slope and slant of writing. Even connections between letters are considered, in that the more connections there are, the more positive and innovative the writer is.
In summary, graphology sounds like an interesting method but I would only use it to supplement what I pick up by other psychic tools. My main connection would be reading a signature or handwritten note via psychometry. I have read jewellery and letters for clients. I have also read photographs by overhead clairvoyancy and read the writing on the back of the photograph by psychometry.