Amazon refers to two very different things:

1. The Amazon River is a massive river in South America, and the largest river by water output in the world. It flows about 4,000 miles mainly through the Brazilian rainforest, carrying more water than the next five river systems combined. The Amazon rainforest surrounding it contains an incredible diversity of plant and animal life: millions of insect species, thousands of birds, and plants found nowhere else on Earth. Scientists sometimes call it “the lungs of the Earth” because its vast forests help cycle gases like oxygen and carbon dioxide in the atmosphere.
2. Amazon is also one of the world's largest companies, started by Jeff Bezos in 1994 as an online bookstore. Today, Amazon sells almost everything imaginable through its website and delivers packages to homes in many countries. Amazon also provides cloud computing services that power many websites and apps, owns Whole Foods Market grocery stores, and produces movies and TV shows. When someone says they're “ordering it from Amazon,” they mean buying something online that will be shipped to their home.