Though the acronym PAC may stand for other terms, it is most prominently used to represent "political action committee". A political action committee is an organization or entity that is formed for the sole purpose of raising funds to support a political ideology or candidate for office.
While PACs exist at many levels, they are often tied to presidential elections. The first PAC was formed in 1944 to help re-elect Franklin D. Roosevelt as president. That committee was called the Congress of Industrial Organizations. While PACs have restrictions on amounts they can give to parties or candidates during elections, independent "super PACs" have existed since a 2010 U.S. Court of Appeals decision, and they can spend unlimited amounts for independent promotion of a candidate.