means differences between cultures.
Culture shock is a term used to describe the anxiety and feelings (of surprise, disorientation, confusion, etc.) felt when people have to operate within an entirely different cultural or social environment, such as a different country or a different state than where they live (e.g. urban southern California vs. rural North Carolina).
The term was introduced for the first time in 1954 by Kalvero Oberg. Other researchers who have subsequently worked on culture shock include Michael Winkelman.
Thanks to wikipedia