Select class when similar are on the page (Read more for example) http://stackoverflow.com/questions/7963821/jquery-select-single-element-with-same-class-as-several-others
$(".show").click(function(){
$(".hidden").toggle();
});
<div id="container">
<div class="box"><!-- box 1 -->
<div class="link"><a href="#" class="show">show content</a></div>
<div class="hidden">this text is hidden</div>
</div><!--box ends-->
<div class="box"><!-- box 2 -->
<div class="link"><a href="#" class="show">show content</a></div>
<div class="hidden">this text is hidden</div>
</div><!--box ends-->
</div><!--container ends -->
.hidden {
display:none;
}