Aldi is the common company brand name of two German multinational family-owned discount supermarket chains operating over 12,000 stores in 18 countries. The chain was founded by brothers Karl and Theo Albrecht in 1946, when they took over their mother's store in Essen. The business was split into two separate groups in 1960, that later became Aldi Nord, headquartered in Essen, and Aldi Süd, headquartered in Mülheim.

A discount store or discounter offers a retail format in which products are sold at prices that are in principle lower than an actual or supposed "full retail price". Discounters rely on bulk purchasing and efficient distribution to keep down costs.