As you have asked about the free online social media marketing course, I am mentioning them, check below for the details

DS106: Digital Storytelling and Social Media

Hubspot’s Inbound Marketing Training Program and Certification
Courses:
Essentials of an Effective Inbound Strategy
Optimizing Your Website
The Fundamentals of Blogging
Amplifying Your Content with Social Media

Social Media Quickstarter
Here is a breakdown of the topics covered in the course:
Social Media 101 (4 chapters)
Facebook (17 chapters)
Twitter (17 chapters)
LinkedIn (13 chapters)
Blogging (3 chapters)

Search and Social Media Marketing for International Business
This course has a lot of great information
Personal branding online
Twitter
Search Engine Optimisation (SEO)
Use of social media for international business development
Facebook
YouTube

Diploma in Social Media Marketing
Get a “diploma” in Social Media Marketing in just 15-20 hours with this free course provided by online course provider ALISON

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