The appendix is a lymphatic organ of the human body and is located between the ileum and the cecum, in the right lower abdomen. The appendix is a lymphatic organ in the human body and is located between the ileum and the cecum. Some people have a relatively short appendix, even less than 2 cm, which is relatively straight, but many people have a long appendix, even up to 9 cm, which curls in the abdominal cavity. The diameter of appendicitis is usually around 5 mm, but when fluid, fecal stones or parasitic infections occur in the appendix, it can lead to a change in the size of the appendix, which can increase in size and diameter and affect the function of the intestine, requiring early treatment.