Viral Marketing

• Viral marketing, facilitates and encourages people to pass along a marketing message. 
• Viral marketing is like a flu and has the audience spread the word about the film in a form of a video or poster which catches the audiences eye. films that have used viral marketing; 

• Batman
• paranormal activity 1,2,3 
• insidious

the dark knight used viral marketing as a way to get publicity, they did this by doing a treasure hunt to get information about it.
People use viral marketing because it is cheap way to advertise it and it will get them more publicity.