Histology is microscopic anatomy of the human body at cellular level and is studied as a basic science in medical curriculum ie during the first or second year while pathology is generally done in third or fourth year after starting medicine surgery and gynecology and knowing about diseased states .
Forensic science is the study of dead tissues and post mortem examinations also are a part of pathology but of a more investigative approach associated with criminology and post mortem examination to find cause of death etc a totally different and vast field by itself as a medical student one went through that in fourth year ,
In these days of great advances in the molecular level of differentiation's pathology at many times decides on the treatment and the word of the pathologist is sacrosanct .
in these days of highly specialized stains in immuno histochemistry and molecular tests and even genetic mutations the differentiation is so vast .
in the early days it was suffice to get a diagnosis of say in breast cancer what type of tissue it was either from glandular called adenocarcinoma or from connective tissue a type of sarcoma called malignant phylloides whose treatment were diametrically opposite today the sub classifications like the hormone status the aggressiveness by grade or by KI 67 range or specialized targets amenable to treatment like Her 2 or epidermal receptors ,the microscopical invasions into blood vessles lymph nodes or lymphatics or nerves are all vital
second opinions are taken at times when pathologists themselves are foxed over certain modulations in tissue
over the years i still remember some eminent pathologists i had the opportunity to work with
i still rememebr getting a bone marrow report on same day something which would never happen abroad !!