It is important to know the differences between British and Amercian English. Although native speakers rarely need to think about questions like this, non-native speakers do. Whenever you need to write something in English you should always decide if you want to write British (UK) or American (US) English.
I am one of the founders and coaches here at Scientific Writing Coach. I am currently a researcher at Stanford University, US. I obtained my PhD from Uppsala University, Sweden and I have a Certificate of Proficiency in English from Cambridge University, UK.