Chocolate agar base is a dehydrated culture medium formulated to support the growth of fastidious bacteria, particularly Haemophilus and Neisseria species. It is a nutrient-rich medium, essentially a variant of blood agar where the red blood cells are lysed (broken down) by heat, releasing essential growth factors like NAD (V factor) and hemin (X factor). This lysis is what gives the medium its characteristic chocolate-brown color