Simply put, Big Data Analytics is more advanced. Big Data Analytics requires a degree or diploma in a STEM (science, tech, engineering, math) field and work experience in technology and data analysis. You would be a fit if you are working in a STEM field and have done some data analysis work, but you want to upgrade to a level where you can use advanced techniques to analyze big data.
Foundations of Analytics welcomes people without this strong background in STEM who want to break into a field working with technology and data or want to do more analytics as part of their current job.
Learn more about the differences here.