We live in a world that is in a constant change. Through of the history we could see how the wars, the poverty, the revolutions, the technology, and the own system, guide the way of humanity. Why the world changes an every moment? Why we live in a deeply inequality society for the most of people? Sociology seems to be a good way to respond these questions, since this is the scientific study of society, patterns of social relationships, social interaction and culture of everyday life. For this, through Sociology we can know the phenomena that occur in the society through history, to take better decisions at present. For example, in the problem of gender inequality at work, with a good sociology investigation we could have a better understanding of this problem. This information could be very important at the time of to make public policies that really help to reduce the salary gap. Consequently, Sociology is an important and indispensable tool if we want a equal and democratic society