"Historical records show that the emergence of aquaculture occurred about 4000 years ago in China, with the cultivation of marine seaweeds and subsequently the cultivation of carps. Since that time until today, many new production and management techniques were created in search to facilitate and improve processes; however, many methods created at that time are used until today. Currently, Chinese production of aquatic organisms almost reaches 40% of the world total production from aquaculture and capture (FAO, 2014). Also according to FAO (2014), world production from aquaculture has already surpassed 50% of total production of aquatic organisms, including fish, crustaceans, molluscs and aquatic plants. The most produced species are carps, tilapias, salmons, red and brown seaweeds, clams, oysters and shrimps. Several studies based on historical data of production and consumption of aquatic food show us that aquaculture has been growing as the production from catching decreases, and the per capita consumption increases as this food source becomes increasingly accessible and health agencies demonstrate their importance in the diet. I, as an engineer of aquaculture, believe in the growth and prosperity of the activity, but everything must be done with planning for sustainable development of the entire production chain. In addition, it is essential to understand the relationship between the environment and all the organisms present in the cultivation system to choose the type of management and the processes to be used. For the activity continues to grow is very important to perform studies about aspects of reproduction, nutrition, genetic improvement, pathology and environmental management. This book provides several studies related to biology and ecology of aquatic organisms grown in these aspects. I hope that this book can help in the understanding of some factors about biology and ecology and help producers with innovations."