New communication technologies innovate rapidly, and issues relevant to new media emerge correspondently. Any 'new' theoretical concepts which try to tackle these issues will be swiftly substituted, but this does not mean that we should discard those obsolete concepts like throwing away our old shoes, but rather take a geneological approach, and try to find out when certain concepts become obsolete and why. 'What is media?' is a fundamental but difficult problem. This article tries to tackle this problem by building up a scaffold with theoretical concepts such as paradigm, media ecology, mediation, remediation, immediacy, hypermediacy, and extended mind. And this proposal should only be considered as an initial attempt.