It seems that people rarely think of appendix and its importance and the only mention of it is when it has to be removed. But, what exactly does this organ do?The appendix is a tube-shaped sac attached into the lower end of the large intestine. Medically, it is known as ‘vermiform appendix’ due to its worm-like shape. This organ was disregarded as useless for a long time and considered as a souvenir of our revolutionary past.