Acute appendicitis is one of the most common surgical abdominal emergencies worldwide, with a lifetime risk of 8.6% for males and 6.7% for females. This compilation discusses how while non-operative treatment of appendicitis has been proposed as an alternative to surgery, appendicectomy remains the mainstay of treatment in most cases and techniques have shifted from open to laparoscopic methods. The current knowledge in pathogenesis, diagnosis, and clinical management of acute appendicitis is also discussed.Next, the authors present an updated review chapter of appendicitis regarding its prevalence and risk factors, particularly how the diagnosis of appendicitis is based on a history of diffuse abdominal pain, which usually starts in the central region of the abdomen and migrates to the lower right quadrant of the abdomen.The residual remnant or stump of the appendix after an initial appendectomy may become inflamed causing what is commonly referred to as stump appendicitis. Treatment with antibiotics may be attempted as an alternative to surgery; however, the vast majority of cases require definitive surgical excision of the remnant appendix. The authors propose that keeping this disease in the differential is important in reducing complications associated with delayed diagnosis.