If you're interested in learning about digital marketing, there are several online courses available that can help you gain the necessary skills and knowledge. Here are a few popular digital marketing courses you can consider:

1. Google Digital Garage: This free online course offered by Google covers various aspects of digital marketing, including search engine optimization (SEO), social media, content marketing, and analytics. It provides certification upon completion.

2. HubSpot Academy: HubSpot offers a range of free digital marketing courses covering topics such as inbound marketing, content marketing, email marketing, social media marketing, and more. They also provide certifications for completing their courses.

3. Udemy: Udemy has a wide selection of digital marketing courses taught by industry experts. Some popular courses include "The Complete Digital Marketing Course," "Social Media Marketing Mastery," "SEO for Beginners," and many more. These courses often come with a one-time fee.

4. Coursera: Coursera offers digital marketing courses from top universities and institutions. Some well-known courses include the "Digital Marketing Specialization" from the University of Illinois and the "Online Marketing Strategies" course from the University of Pennsylvania's Wharton School. Coursera courses can be accessed for free, but you may need to pay for a certificate.

5. LinkedIn Learning: LinkedIn Learning provides a wide range of digital marketing courses taught by industry professionals. Topics covered include SEO, social media marketing, content marketing, Google Analytics, and more. A subscription is required for access to the courses.

Remember to research each course, read reviews, and consider your learning style and objectives before choosing the one that best fits your needs. Additionally, staying updated with industry trends, blogs, podcasts, and attending webinars can further enhance your digital marketing knowledge and skills.