What is the meaning of "Mobility" in applying for postdoc positions I am going to apply for postdoc position in math. I have been asked for some documents  titled "Previous Mobility" and "Scientific background". I do not know what I can put in Previous Mobility, because I think it is almost the same with scientific background. I appreciate your assistance in this regard.
I took a look at about five first postdoc positions at jobbnorge and did not find the word "mobility" there, so maybe it is not standard. I did not look at the application form.

My assumption (I am Finnish, living currently in Norway, so cultural proximity maybe gives me some credibility) is that it means the locations where you have stayed for academic purposes. Since your employment history is already explained elsewhere (I guess), you would want to list any longer research visits to universities you are not employed at and institutes (Poincaré, Mittag-Leffler, etc.). If you had an external stay as a part of your PhD, list that, too.

I do not know about how short a visit you should list or if you should list being an exchange student during you bachelor or master studies.

One motivation is probably to see if the job candidate has been outside Norway on academic purposes. If you are a foreigner, this is not hard. Lots of experience at diverse places or presence at a prestigious institute might be viewed favourably, too, who knows.