Amazon has provided the world with a way to access things that are desired without leaving the comforts of home. It not being the first, but becoming a strong share holder of the market.

i personally have bought things ranging from used sega genesis games to brand new shoes from online websites.

The great thing about the front page of Amazon is that it shows a variety of products, everything from sports equipment to computer software. it has illustrated pictures of the products.

None the less, there is one downside to it. The purchase of online products has a negative effects on local retailers. Because Amazon sells mostly new products, it takes away a specific niche demand of online shopping.

Relating amazon to ebay, ebay sells many auctioned off products. it provides new and used products that gives a broader product base.
Much stuff that is purchased online is stuff that can not be normally purchased at retailers. specifically like things like used video games no longer sold or old toys or antiques.

Though amazon does provide much variety of new products and ebay doesn't, ebay provides a market where things can be purchased easily that are relatively old.

All these markets are great, it is just using the optimum tool for the item you are looking for.

retail markets are great for instant gratification if you need the product now. For instance, clothing, depending on the brand.
Amazon is good if you cant find the product locally. For instance, books, sports equipment, and computer software.
Ebay is great to find products that are used/new and are relatively hard to find and are sold by other people on the web. For instance, used zippo lighters, used video games, old gaming systems, and nostalgaic items.