What is democracy?
The term democracy is derived from the ancient Greek term demokratia. The demo part means people and the kratia part means power or rule. All together, democracy means rule of the people. The people’s power comes from the ability to vote. The people who have the power, are considered to be those who are allowed to vote. Another term for those who are allowed to vote is the franchise.
The franchise has dramatically changed over time. It used to just be wealthy, old, white men. In the UK, and in most other democracies, the franchise eventually widened to include all men and women over the age of 18, with a few exceptions like prisoners and those convicted of electoral fraud. The franchise is generally quite similar across most democratic countries, although in parts of South America and in Austria and Norway, 16 year olds can vote.
The first system that could be reasonably described as a form of democracy was that practiced by the Athenians beginning between 600 and 400 BC. All the property owning men would gather in the square, they would debate what ever the topics of the day were, before voting, usually by choosing which side of the square to go. The citizens were literally doing the day-to-day business of the state. This was time consuming and required knowledge of the topics at hand. This kind of system became less and less feasible as society became more complex, and as the property owning men began to spend more time doing other things like working in factories, starting businesses and doing leisure actives.
Eventually a distinction emerged between two types of democracy: direct and indirect.
If you are interested, this Britannica article dives into some of the major practical questions about how this kind of democracy works in practice.