527s -- A type of tax-exempt organization, named after a section of the U.S. tax code, created primarily to influence the nomination, election, appointment or defeat of candidates for public office. Since they do not give money directly to candidates, 527s avoid campaign finance regulations rules and limits. For example, Swift Boat Veterans for Truth.

Advocacy -- An organized effort to actively and publicly support and promote a particular set of issues or course of action, advocacy is expected to be non-deceptive and in good faith.

Common Good -- Benefiting the majority of members of society.

Corporate Interest -- Lobbying on behalf of a business or industry.

Earmark -- A narrowly focused appropriation of government money, usually attached to appropriations bills by lawmakers to fund pet projects within their districts.

Expenditure Test -- A law enacted in 1976 establishes a ceiling for lobbying expenditures by charities and/or nonprofits.

Front Groups -- Any entity set up by and controlled by another organization. A front organization hides the parent group's name, giving any research or political actions the appearance of independence.

Gift Ban -- To prevent corruption and even the appearance of corruption, lobbying and political regulations ban or limit the amount of gifts lawmakers can accept. Regulations vary by state and some lawmakers have self-imposed limits or bans.

Graft -- The act of acquiring money or advantage by dishonest or unfair means, especially through the abuse of one's position or influence in politics.

Grassroots Lobbying -- An indirect lobbying movement organized by a network of citizens intent on influencing politics through non-violent action at the community level. For example, door to door campaigns.

Hard Money -- Direct donations from individuals, organizations, Political Action Committees and political parties that are subject to campaign finance regulation rules and limits.

Influence Peddling -- The practice of using money or connections with people in authority to obtain favors or preferential treatment.

Lobbying -- Coined by Ulysses S. Grant for people who lingered in the lobby of the Willard Hotel -- located across the street from the White House -- hoping to catch him as he went there to enjoy cigar and drink, the term lobbying covers all acts aimed at influencing government action.

Political Action Committee -- The name commonly given to a private group organized to elect or defeat government officials in order to promote legislation, often supporting the group's special interests. For example, MoveOn.org.

Political Corruption -- Influencing the political system through bribery, intimidation, extortion, vote buying, destabilization, or influence peddling.

Public Interest -- Lobbying on the behalf of issues that affect the welfare of the general public.

Quid Pro Quo -- An exchange of an act for a promised act in return -- Latin for "something for something."

Revolving Door -- Term coined to describe lawmakers and legislative staffers who leave office only to return to Capitol Hill as a lobbyist. Although once frowned upon, the practice has become accepted and more common. Lobbyists generally make significantly more money than government employees.

Right of Petition -- The right, guaranteed under the U.S. Constitution's First Amendment, to request in person or in writing the government redress of grievances.

Soft Money -- Huge unlimited donations from corporations, wealth individuals and labor unions to the national political parties, supposedly for generic "party building" activities.

Special Interest -- A person, group, or organization attempting to influence legislation in favor of one particular interest or issue. For example, the National Right to Life Committee.

Substantial Test -- Lobbying by nonprofit organizations/charities cannot be a "substantial part" of an organization's activities.

Think Tank -- A research organization that seeks to influence legislation and public opinion through regular releases of detailed reports and supporting research to the media, lawmakers and the public.

Trade Group -- Group that represents the interests of a particular trade or industry. For example, the National Milk Producers Federation.