Inbound marketing

This is a more "modern" approach to Marketing, in which companies passively let users find them. A clear example is having a website findable through a search engine. When people search for keywords, they will find your offer.

It is radically different from Interruption Marketing, since you assume the customer was looking for you without knowing they were. This is one of the reasons why so many marketeers focus on search engine optimization (see: The role of search engines for scientific marketing).

However, other paths include leveraging non-paid social media posts, blogging, etc. Invitations to public speaking (not necessarily a paid presentation at a conference).

In the end, everything which organically shares value with your target customers and that allows them to find you. This is what ElveSys does with its collection of videos about microfluidics, for example.