Digital marketing involves promoting products and services using digital channels to reach large audiences. It includes attracting audiences on social media platforms like Facebook, Instagram, Twitter, and YouTube. The main types of marketing are traditional offline marketing using methods like direct mail, print ads, and outdoor advertising, and online digital marketing using digital channels and strategies to optimize reach, leads, conversions, and sales online. Some key benefits of digital marketing are its global reach, lower costs compared to traditional methods, and ability to effectively target audiences.