Cystine tryptic agar (CTA) which is also referred to as cystine trypticase agar was created by Vera as an semi-solid growth medium to identify and maintain the health of microorganisms for long time period of time when stored at suitable temperatures. It’s used for determination of the motility of bacteria and, when combined with carbohydrate, is involved in the fermentation process and the differentiation of microorganisms that are fastidious, such as Neisseria and streptococci, as well as pneumococci and non-spore-forming anaerobes.