Association of like-minded people organized with the purpose of seeking and exercising political power. A party can be distinguished from an interest or pressure group, which seeks to influence governments rather than aspire to office, although some pressure groups, such as the Green movement, have over time transformed themselves into political parties.
Although politics, as an activity, has been practiced for thousands of years, political parties seem to have been largely a product of the 19th century. Although the US constitution contains no reference to parties, the Republican and Democratic parties became essential elements of the political system, reflecting the country's history and social and economic structure. The one-party state, in which party and state institutions became enmeshed, was the distinguishing feature of the political system established in Russia by Lenin (and later Stalin) after World War I.