difference between while and when

[saidon]

How is while differnt from when?

Which sent. is correct from the below ones and why?

1. I was living here while I was in school.
2. I was living here when I was living here.

[Tdol]

I presume you meant this:
1. I was living here while I was in school.
2. I was living here when I was in school.

There's no real difference here. If an action is short in duration, then 'when' is the natural choice.