Who makes the decisions in a democracy?

In the traditional meaning of democracy, all members of a group contribute to the decision making process, typically through voting. In fact, the term "democracy" comes from the Greek demokratia, meaning "people's rule." In reality, there have been very few true democracies due to the difficulties of implementing this form of government on such a large scale.
In Ancient Greece, where democracy originated, the only real acting members of a democracy were adult males of wealth. Children, for obvious reasons, were not allowed to vote, but neither were women or slaves. In more modern times, democracies exist based on the agreement that all persons, regardless of gender, class, bodily ability, or ethnicity, are given the right to vote. In the United States, this is the understanding, but it's much more complicated in implementation! Imagine if a group of one hundred people broke up into groups of ten and each elected an individual to vote in a committee of the ten representatives.  This is similar to the representative democracy of the United States, where the masses vote for people who will represent them and vote on their behalf. 
https://www.britannica.com/topic/democracy