The innovation of this book is the study of insect communities and their interactions between the same species or with other species and animals. This is very important as we are as human beings much affected by insects specially those sharing our food by feeding on the same plants and animals we use for our nutrition and others are acting as vectors transmitting diseases which affect our health. The book also elaborate the growth of their populations and the factors that lead to their increment and the factors that retard their population growth. And also elaborated the competition between the individuals of the same species and with others different. Also the book gone through different theories and models and equations that to be used to calculate the growth of insect populations which give the prediction of the levels that insects will reach to extend affecting our lives or causing famines to populations. The book gives accounts to all environmental factors and ranges that affect the growth of populations and how it could be used to check their numbers. It elaborated the role of natural enemies for controlling noxious insects that affecting our life.