What is e-commerce?

E-commerce refers specifically to the buying and selling of products or services conducted over the internet. This encompasses a wide range of online transactions, including shopping on retail websites, auction sites, and even service-based platforms. E-commerce has transformed commerce by allowing businesses to reach customers globally, streamline transactions, and provide convenience to consumers who can shop from anywhere with an internet connection.

While the other choices touch on aspects of online marketing and retail, they do not define e-commerce itself. Email marketing is a method of reaching customers but is not inherently about selling products or services. Similarly, using social media for advertising supports e-commerce but does not equate to it. Finally, physical retail refers to traditional, in-person shopping, which is a separate concept from e-commerce. The correct answer captures the essence of e-commerce as an online marketplace where transactions occur.