Voting is the process of choosing officials or policies by casting a ballot, a document used by people to formally express their preferences. Republics and representative democracies are governments where the population chooses representatives by voting.

The procedure for identifying the winners based on votes varies depending on both the country and the political office. Political scientists call these procedures electoral systems, while mathematicians and economists call them social choice rules. The study of these rules and what makes them good or bad is the subject of a branch of welfare economics known as social choice theory.

In smaller organizations, voting can occur in many different ways: formally via ballot to elect others for example within a workplace, to elect members of political associations, or to choose roles for others; or informally with a spoken agreement or a gesture like a raised hand. In larger organizations, like countries, voting is generally confined to periodic elections.

In a democracy, the government is elected by the people who vote in an election: a way for an electorate to elect, that is choose, from several different candidates. It is more than likely that elections will be between two opposing parties. These two will be the most established and most popular parties in the country. For example, in the US, the competition is between the Republicans and the Democrats. In an indirect democracy, voting is the method by which the person elected (in charge) represents the people, whilst making decisions. Direct democracy is the complete opposite, the people make the policy decisions directly without selecting a representative to do it for them.

A majority vote is when more than half of voters vote for the same person or party. However, whilst it is usually said each individual's vote does count, many countries use a combination of factors to decide who has power, not the at-large "popular vote". Most influential of these factors are districts that divide the electorate. For example, in the UK a party winning plurality in a majority of constituencies wins majority government, but they may not always have the most individual votes (i.e. they may have lose the popular vote but still win the seat count). (It is also possible for a party to win plurality in a minority of constituencies (but more than any other one party) and thus win minority government.)

All modern liberal democracies use voting by secret ballot to prevent individuals from becoming influenced by other people and to protect their political privacy. The objective of secret ballots is to try to achieve the most authentic outcome, without any risk of pressure, threat, or services linked to one's vote; this way, a person is able to express their actual preferences.

Voting often takes place at a polling station but voting can also be done remotely by mail or using internet voting (such as in Estonia). Voting is voluntary in some countries, like the UK, but it may be required by law in others, such as Australia.

There are many electoral methods. The purpose of an election may be to choose one person, such as a president, or a group, such as a committee or a parliament. In electing a parliament, either each of many small constituencies can elect a single representative, as in Britain; or each of a lesser number of multi-member constituencies may elect two or more representatives, as in Ireland; or multi-member districts and some single-member districts can be used; or the entire country can be treated as one "at-large" district, as in The Netherlands.