The blue bin (or blue box) is the container for household recyclable materials, one of the most recognized symbols of municipal recycling programs. Blue box recycling began in Kitchener, Ontario in 1981 and spread across Canada. Acceptable materials typically include paper, cardboard, plastic containers, glass, and metal cans, though specific rules vary by municipality based on local processing capabilities. Contents are collected, sorted at recycling facilities, and sold to manufacturers who use them as raw materials. Effective recycling requires residents to properly sort materials—contamination (putting wrong items in the blue bin) can render loads unrecyclable.