The term Democracy comes from the Greek words demos (people) and Kratos (power). In its literal meaning, democracy means the "rule of the people. In fact, it is a form of government in which all eligible people have an equal say in the decisions that affect their lives. Democracy as a political systems existed in some Greek city-states, notably Athens following a popular uprising in 508 BC. Equality and freedom have both been identified as important characteristics of democracy since ancient trines. These principles are reflected in all citizens being equal before the law and having equal access to legislative processes. For example, in a representative democracy, every vote has equal weight, no unreasonable restrictions can apply to anyone seeking to become a representative, and the freedom of its citizens is secured by legitimized rights and liberties which are generally protected by a constitution. There are several varieties of democracy, some of which provide better representation and more freedom for their citizens than others. However, if any democracy is not structured so as to prohibit the government from excluding the people from the legislative process, or any branch of government from altering the separation of powers in its own favor, then a branch of the system can accumulate too much power and destroy the democracy. Separation of powers is a model of governance under which the state is divided into branches, each with separate and independent powers and areas of responsibility so that no one branch has more power than the other branches. The normal division of branches is into an executive, a legislature, and a judiciary.