A primary is where certain voters cast a ballot for a candidate within one party; whereas, a caucus is where party members go to hear speeches and vote for someone represent a candidate at a national convention.

"In U.S. politics and government, caucus has several distinct but interrelated meanings. One is for a meeting of members of a political party or subgroup to coordinate members' actions, choose group policy, or nominate candidates for various offices." "A primary election (nominating primary) is an election in which voters in a jurisdiction select candidates for a subsequent election. In other words, primary elections are one means by which a political party nominates candidates for the following general election. "Primaries" are common in the United States, where their origins are traced to the progressive movement. There, primary elections are conducted by government on behalf of the parties. Elsewhere in the world, the nomination of candidates is instead usually the responsibility of the political party organizations themselves and does not use the public apparatus. Besides primaries, other ways that parties may select candidates include caucuses, conventions, and nomination meetings. Historically, Canadian political parties chose their candidates in party meetings in each constituency. Canadian party leaders are elected at leadership conventions, although some parties have abandoned this practice in favour of one member, one vote systems." Both are used to decide political candidates, caucuses are generally used to nominate candidates and primaries are used to elect on of the candidates nominated so he/she can run for the office; eg. President. http://en.wikipedia.org/wiki/Caucus http://en.wikipedia.org/wiki/Primary_election

A primary is simply an election. In this election, voters cast a ballot for the candidate they wish to have represent their party in the election. A caucus is more of a meeting. A party will gather to hear candidates speak about their ideas, goals, and plans. This is an opportunity for the candidates to flesh out their platform as well as a chance for voters to listen and start to gather information on whom they might chose to represent their party.

A primary is a type of election, where members of a political party determine who their delegatse vote for at a convention. A caucus is a forum style of primary, where instead of using a secret ballot, a show of hands is used. It's not as simple as this... if the candidate you support can't get 15% of the groups vote, you have to change your vote, or not vote at all. It's explained here: http://www.pbs.org/newshour/bb/election/iowa-newhampshire/iowa-procedures.html

A primary is an election open to the public at large within certain restrictions: must belong to the party holding the primary (most states) or must not have voted in another open primary in that state. A caucus is a selection done by a group of people cjosen for that purpose. Some states have arcane rules about getting up and moving to another side of the room but generally a cuacus is NOT via secret ballot while a primary is always via secret ballot .

This is more of a quest for clarification on the original question... So, is a State such as Texas or Colorado, that has primaries and caucuses, divided into regions that provide delegates from one or the other? For example, if my precinct holds a caucus, am I restricted from voting in a primary? Or the reverse, if my precinct holds a primary, am I then restricted from actively participating in a caucus? I would think so, otherwise there would be double counting. Very confusing, nonetheless...

primary - voting is done in a secret way and in Caucus has no secrecy in electing the candidates. http://www.differencebetween.net/business/difference-between-caucus-and-primary/