MSD

follow the link and descover what MSD is

http://en.wikipedia.org/wiki/Media_system_dependency_theory

main points to use:

• What is Sandra Ball-Rokeach and Melvin Defleur's Media system dependency theory (MSD), or simply media dependency?
• What are the 3 main relationships between components
• What are Media needs and media dependency?
• What is New media dependency (NMD)?
• What is the difference and effects of  'The microlevel' and  'The macrolevel'

you just need an overall understanding of these key points and be able to mention them in terms of the impact of media/ new media on people and society