How can i change a pictures format/type?

How i do to change a BITMAP format to a JPEG format??? or is that i can't change it?How can i change a pictures format/type?
The easiest way is to open it in your Paint program, then go to



File%26gt; Save As%26gt; and in the drop down menu in that window, select ';JPEG {.jpg, .jpeg)



then click Save.