E-marketing refers to using electronic media and applications to conduct marketing activities. It involves using digital tools like websites, social media, and online ads to reach customers. E-marketing allows companies to globally market their products and services in a more cost-effective manner compared to traditional marketing. It provides advantages like 24/7 accessibility, lower risks, and the ability to quickly respond to customers and measure marketing efforts. However, e-marketing also faces disadvantages such as technological issues, inability to physically see products, and increased price competition globally.