Moving abroad and experiencing new culture ushers in a lot of exciting and disorienting new experiences.
You are forced outside of your comfort zone, and in a new culture and space, you have both the freedom to reinvent yourself, and also the loss of being "known" in the way you were back home.
When people talk about culture shock, this is often what they're referring to: the major differences in how people structure their daily lives and social mores in other countries.
But you can also experience culture shock when you return home from a stint of traveling, seeing your own home through new eyes can be surreal.
After living in Australia for some time, I went back to Italy and I couldn't believe Italians can't stand in line while waiting for something. We spread all around like a herd of sheep.
Food was even better than I remembered though, especially my grandmother's stuff.