what is the difference traditional marketing and modren marketing and which is one is bettar?

Traditional marketing is more on print, radio and tv ads and the like. Modern marketing is more bound of using the internet as your new media in promoting your business.

Would you say that nowadays a lot has shifted into social media as a primary marketing strategy, while that wasn't so much the case even just a few years ago?

The big diffrence in between the traditional marketing and modern marketing was created by the technically suported activities. Today marketing starategy takes concern of brand image building, user's experience, response graph and the feedbacks etc. Earlier, it was very tough to pin point the focus upon critical and faded issues.