How with jquery recognize to witch section the page is scrolled now?
I have page more or less like that:

    <nav style="position:fixed;top=0;left=0;width:100px;">
      <a class="one" href="#one">One</a>
      <a class="two" href="#two">Two</a>
      <a class="three" href="#three">Three</a>
      <a class="four" href="#four">Four</a>
      <a class="five" href="#Five">Five</a>
    </nav>
    <section style="margin-left:120px;height:550px;">
      <a name="one" id="one"></a>
      Content of section one ...
    </section>
    <section style="margin-left:120px;height:350px;">
      <a name="two" id="two"></a>
      Content of section two ...
    </section>
    <section style="margin-left:120px;height:750px;">
      <a name="three" id="three"></a>
      Content of section three ...
    </section>
    <section style="margin-left:120px;height:450px;">
      <a name="four" id="four"></a>
      Content of section four ...
    </section>
    <section style="margin-left:120px;height:250px;">
      <a name="five" id="five"></a>
      Content of section five ...
    </section>

Nav is all time visible, and when user click a link it is getting .active class in jquery. But when he scroll page, i want to change .active link depending on a section witch is first in visible area of window. I tried to play with $(window).scroll() and $(link.hash).offset().top, but to be honest i have no idea how to manage it to work properly.
How with jquery recognize to witch section the page is scrolled now?
===

I have page more or less like that:

    <nav style="position:fixed;top=0;left=0;width:100px;">
      <a class="one" href="#one">One</a>
      <a class="two" href="#two">Two</a>
      <a class="three" href="#three">Three</a>
      <a class="four" href="#four">Four</a>
      <a class="five" href="#Five">Five</a>
    </nav>
    <section style="margin-left:120px;height:550px;">
      <a name="one" id="one"></a>
      Content of section one ...
    </section>
    <section style="margin-left:120px;height:350px;">
      <a name="two" id="two"></a>
      Content of section two ...
    </section>
    <section style="margin-left:120px;height:750px;">
      <a name="three" id="three"></a>
      Content of section three ...
    </section>
    <section style="margin-left:120px;height:450px;">
      <a name="four" id="four"></a>
      Content of section four ...
    </section>
    <section style="margin-left:120px;height:250px;">
      <a name="five" id="five"></a>
      Content of section five ...
    </section>

Nav is all time visible, and when user click a link it is getting .active class in jquery. But when he scroll page, i want to change .active link depending on a section witch is first in visible area of window. I tried to play with $(window).scroll() and $(link.hash).offset().top, but to be honest i have no idea how to manage it to work properly.