An electorate is a body of people allowed to vote in an election. In the United States, when you turn eighteen, you may join the electorate and help choose a president.
The word electorate is especially important for those people who are not a part of it. For instance, women in the United States were not part of the electorate until they were allowed to vote in 1920. Being a part of the electorate is important because it gives you a chance to elect — or choose — who you want to represent you in your government.