What Is E-commerce? The Dictionary says: e-commerce: Commerce transacted electronically, as over the Internet. Synonyms include: e-commerce, electronic Commerce, E-commerce, ecommerce, online retail, online trading, and selling online. Selling and transacting like this can be done thanks to the World Wide Web, which is the global combination of links, information, web pages and e-commerce websites. All of this is delivered to us via the Internet, an infrastructure of computers all linked together.