Social media marketing refers to the use of social media platforms such as Facebook, Instagram etc., as a part of digital marketing strategy to promote your brand, product or business.
Advertising is using a channel to showcase your message for a price. It is used to reach people faster and for brand awareness. Advertising is an audio or visual promotion of your brand, product or services
Content marketing is a strategic marketing approach focused on creating and distributing valuable, relevant and consistent content to attract and retain a clearly defined audience - and ultimately, to drive profitable customer action.