Other forms: labor unions
A labor union is a group formed by workers that helps them protect their rights and more easily bargain for better pay and working conditions. Most police officers and firefighters belong to unions.
The earliest labor unions formed in Britain (where they're more commonly called "trade unions") during the 1700s. The Industrial Revolution created all kinds of jobs for people, but it also presented new dangers and risks for workers. Labor unions, then and now, allow laborers to collectively form what's know as a bargaining unit, giving them a larger voice and more power as they seek workplace safety, benefits like healthcare, and higher wages.