The 4 P's of online marketing are Product, Price, Place, and Promotion. Product refers to the goods or services offered by a business, Price involves determining the cost of the product or service, Place focuses on the distribution channels used to reach customers, and Promotion involves the various marketing tactics used to raise awareness and drive sales, such as advertising, social media, and content marketing. Together, these elements form the foundation of an effective online marketing strategy to attract and retain customers in the digital landscape.