Amazon.com's product lines available at its website include several media (books, DVDs, music CDs, videotapes and software), apparel, baby products, consumer electronics, beauty products, gourmet food, groceries, health and personal-care items, industrial & scientific supplies, kitchen items, jewelry, watches, lawn and garden items, musical instruments, sporting goods, tools, automotive items and toys & games.
Amazon allows users to submit reviews to the web page of each product. Reviewers must rate the product on a rating scale from one to five stars. Amazon provides a badging option for reviewers which indicate the real name of the reviewer (based on confirmation of a credit card account) or which indicate that the reviewer is one of the top reviewers by popularity. Customers may comment or vote on the reviews, indicating whether they found a review helpful to them. If a review is given enough "helpful" hits, it appears on the front page of the product. In 2010, Amazon was reported as being the largest single source of Internet consumer reviews.