There are at least two ways in which written communication differs from one culture to another in the business context.
First, there is the obvious difference of language. Different cultures have different languages and written communication must be in the proper language.
Second, and much more importantly, there can be vast differences in what various cultures expect to see in written business communications. Some cultures are what is called “low-context” cultures. They expect many things to be put in writing and very little to be left up to the personal discretion of the person making a decision. For example, in such a culture, the rules for something like requesting vacation time will be very explicit. There will be written communications in the form of employee handbooks that set out the rules very clearly. This is different from a high-context culture in which much more is left out of written communications and is at the discretion of the person making the decision. There are also differences in how direct one may be in written communications. Some cultures expect these communications to be rather blunt and to make their meaning explicit and clear. Other cultures find this sort of thing rude and prefer more nuanced writing that does not say things so explicitly.