WASHINGTON - As millions of Americans vote for their next president tomorrow, here are some of the frequently asked questions about the elections:

WASHINGTON - As millions of Americans vote for their next president tomorrow, here are some of the frequently asked questions about the elections:

Types of elections in the United States?

There are two basic types of elections - primary and general. In addition to these elections held in even-numbered years, some states and local jurisdictions also hold "off-year" elections in odd-numbered years for their elected officials.

A primary election is a nominating election in which the field of candidates in the general election is chosen. Victory in a primary usually results in a candidate being nominated or endorsed by a political party for the general election.

The purpose of a general election is to make a final choice among the various candidates who have been nominated by parties or who are running as independents or, in some cases, write-in candidates.

In addition, many states provide for special elections, which can be called at any time, to serve a specific purpose, such as filling an unexpected vacancy in an elected office.

What are midterm elections?

The elections in which Americans vote for their congressional representatives but not for their president are known as midterm elections. Every two years Americans elect members of the US House of Representatives to two-year terms and about one-third of their US senators, who serve six-year terms.

What is a convention?

Conventions are meetings sponsored by political parties for their members to discuss issues, candidates and campaign strategies. These meetings can last several days.

In presidential elections, after state primaries each party holds a national convention to formally select the presidential nominee - usually the candidate who secured the support of the most convention delegates. Typically, the presidential nominee then chooses a running mate to be the party's candidate for vice president.

The Democratic National Convention was held in Denver on August 25 to 28. The Republican National Convention was in St Paul, Minnesota, from September 1 to 4.

What is a caucus?

A caucus is a meeting at the local level in which registered members of a political party in a city, town or county gather to express support for a candidate.

Requirements for voting, running for office. Who can vote?

American citizens aged 18 and older can register to vote. To register, voters must meet the residency requirements of their states, which vary, and comply with voter-registration deadlines.

What are the requirements for running for elected office in the US?

Each federal elected office has different requirements, which are laid out in in the US constitution.

A candidate for president must be a natural-born citizen of the US, be at least 35 years old, and have been a resident of the country for at least 14 years. A vice president must meet the same qualifications. Under the constitution, the vice president cannot be from the same state as the president.

Scheduling elections. When are general elections held?

They are held on the first Tuesday after the first Monday of November. The 2008 election will be held tomorrow (November 4).

Why are general elections held on the Tuesday after the first Monday in November?

For much of US history, America was a predominantly agrarian society. Lawmakers considered their convenience when choosing a November date for elections as the easiest month for farmers and rural workers to go to the polls.

Source: Distributed by the Bureau of International Information Programmes, US Department of State.