If the government has complete and absolute power over the people, that's totalitarianism. This is a repressive, unfree type of society.
A democracy is a society in which people have a say in their government and elect their leaders. The opposite is totalitarianism: a totalitarian society is usually ruled by a dictator, and there is very little or no freedom. In totalitarianism, the government controls almost every aspect of life. There is no free speech or freedom of the press: certain religions and ideas may be banned. George Orwell's novel 1984 was a brilliant look at a world of totalitarianism.