Democracy is defined as for people ,by people and of people .Democracy is a situation in which the government is voted by the people and the representatives rules on the behalf of people. It is their responsibility to raise voice of the people who have selected them and enabled them to make rules for everyone.
After reading the above lines one thing is for sure that questions like how these representatives are selected and how the make laws for everyone have must crossed your mind so let me answer these things .They are selected by an process called election and they rule according to the constitution.
Elections are a process of selecting the candidates by voting and in democracies like of India who so ever gets maximum number of votes win. In this way the get a tenure of five years to represent their people.
Constitution is the set of rules according to which the decisions are taken in a democracy. Every country has its own Constitution in few countries like India the constitution is a mixture of different countries constitution and this is the one thing that makes Indian constitution robust and greatest of all.