English has largely dropped these directional words now, but var corresponds to where, vart corresponds to whither (to where), and varifrån corresponds to whence (from where). Equivalents in English and Swedish exist for here and there, too.
Who/whom is to do with cases, so: who is used like I, he, we, or they. Whom is used like me, him, us, or them. Whose is used like my, his, our, or their.