Products are categorised into various types based on their relation with microbial growth. There are three types of products. The first is Growth associated products then followed by Non-Growth associated products and Mixed mode product formation. In growth associated products, product is formed along with the growth of the microbial cells and product concentration is almost directly proportional to microbial growth rate. Whereas in non-growth associated products, product formation is nowhere related with growth rate of microbial cells but its a function of cell concentration and we can say that product formation and microbial growth rate are almost inversely proportional to each other.