This document discusses various types of pseudocysts and true cysts found in the body. It begins by defining the key differences between a true cyst and a pseudocyst. Pseudocysts are lined by granulation and/or fibrous tissue rather than an epithelial cell layer. The document then classifies and describes different types of pseudocysts including traumatic bone cysts, aneurysmal bone cysts, and developmental cysts. It provides details on the etiology, location, patient demographics, clinical presentation, radiographic features, histopathology and treatment for each type.