This document discusses glioblastoma multiforme (GBM), a highly aggressive type of brain tumor. It begins with an introduction that defines GBM and notes its prevalence. The document then covers the etiology, classification into primary and secondary types, signs and symptoms, diagnosis, and standard treatment approaches. The prognosis for GBM is generally poor, with median survival being approximately one year. Risk factors include older age and certain genetic disorders. Surgery, radiation therapy and chemotherapy may be used to try to improve outcomes, but prevention is not currently possible given unknown causes. In conclusion, GBM originates from glial cell precursors and causes variable symptoms depending on location and effects on brain function.