Hot versus cool media
Media scholar Marshall McLuhan created two categories: hot vs. cool media.
Hot media is that which engages one sense completely. It demands little interaction from the user because it 'spoon-feeds' the content. Typically the content of hot media is restricted to what the source offers at that specific time. Examples of hot media include radio and film because they engage one sense of the user to an extent that although the user's attention is focused on the content, their participation is minimal.
Cool media generally uses low-definition media that engages several senses less completely in that it demands a great deal of interaction on the part of the audience. Audiences then participate more because they are required to perceive the gaps in the content themselves. The user must be familiar with genre conventions in order to fully understand the medium. Examples: TV, phone conversations, comic books.