I read this question and know What's the difference between 301 and 302 in HTTP but my question is What's the difference between 301 and 302 in HTTP for Search engine?
@dani its not true...
It is called server status code and each search engine treat them as per below list:
http://en.wikipedia.org/wiki/List_of_HTTP_status_codes
301 status code means the page has permanently moved to another location and search engine will pass old page value, rank and other important stuff to that newly created page. To obtain the benefit of this, one need to permanently move old page to newly created page.
302 status code means, the page is temperately not available, this code will acknowledge the search engine about temporally unavailability of the page.