The term "Culture shock" suggests that it's something that happens quickly, however that isn't always the case. It can be more of a process and something that takes time to develop. You might not notice any shock. At first you are more likely to be excited about being in a new place.
Over time though things can get to you and life becomes more routine.
Here's a list of cultural difficulties I and many others experienced while living/teaching English in Asia (China, Korea, Japan and Taiwan). Problems with schools/employers can be one problem and the other can be culture.
Without a knowledge of the local language you'll be in for some difficulties and frustrations. Consider learning the language.
It's different and you won't have the selection that you are used to. Some people struggle with it. A number of teachers in the interviews commented on this. Vegetarians can have a difficult time too.
Roles are in most cases now reversed. You'll get to experience what it is like to be a minority. Many people have no problem gawking at foreigners. Staring is commonplace.
Kids will want to touch your arm hair and perhaps your nose.
5. Round about speaking
This is like the third language; it's not your native language and it doesn't seem to be theirs or is it? Expect indirect communication at times and be able to read between the lines.
Large populations and cultural differences mean less space. You may find that your personal space will be invaded from time to time.
Peoples manners are different. Sometimes they will seem better, more refined (often in Japan) and other times similar to rednecks. For example, in China some people can be rather curt and you won't hear so many "thank you's".
7. Cutting and pushing
In China you're likely to at one time or another to be the recipient of pushing or someone cutting in front of you or someone else in line. Some of the older folks in Korea also seem to enjoy pushing.
In Asia smoking in public is more acceptable than in the west. While it's not allowed in all public places the laws are certainly more relaxed. People will light up in the local restaurants. And in some places throw the butt on the floor. In Korea they love to smoke in the bathroom.
Korean silkworms anyone?
In Taiwan (outside of Taipei) you'll find red betel nut stains on the streets. In Korea and China it's quite common to see people spitting in public.
This is common in Korea and China. It's like there's a competition to see who can hawk the loudest.
People, which are often kids and older folks seem more comfortable farting in public. Older folks walking by seem to have no problem letting one rip as they walk by you on the street. Kids in the classroom also seem to be immune to the foul aroma someone left in the room. Nobody will say anything. Perhaps it's more acceptable.
Larger populations bring more pollution. In some places you'll find trash in the streets and sometimes on the restaurant floor (China). In Korea you'll find it difficult to even find a public waste basket on the street.
Industrialized nations have more factories, often less regulations and create more air pollution. Taiwan used to have many factories, but now most of them have moved to China.
14. Loud speakers
Sometimes it seems like anybody has one, from the fruit guy on the street to the baker in the supermarket.
Come the season they hit the streets with vans and loudspeakers.
16. Music from stores
Some stores on the street will play blaring loud music. It's as if they think the louder they play the music the more customers they are going to get.
Discrimination can be practiced more openly than you are used to.
Teaching abroad and traveling abroad are not the same either. Being open to new experiences is possibly the greatest asset one can have for a fulfilling time abroad.