Importance of cache in Page Rank

It is not possible that your page rank will increase without having indexed your site, or shall we say cached, because search engines like Google, Yahoo and MSN will crawl or "spider" your site first slowly but surely. Without being indexed and included into the search engine list, your PR cannot increase or let's say we call "n/a". It is important that you must first index/cached your website through Google Webmaster tools by just needing verification either meta tags or attach a verification code in your HTML of website.

We do need SEO for our websites, but without being indexed your SEO work will be very useless. So we learn everything how we need our site to be indexed in different search engines before we try to increase our PR.