The difference between html empty link href='#' and href='javascript:void(0)'

#contains a location information
The default anchor is #top, which is the top of the webpage
And javascript:void(0) only represents a dead link
This is why sometimes the page is very long and the browsing link is obviously #but it jumps to Top of page
This is not the case with javascript:void(0)
So it is best to use void(0) when calling a script
You can use the following example to test it:

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"</span><span style="color: #0000ff;">></span> 
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">xmlns</span><span style="color: #0000ff;">="http://www.w3.org/1999/xhtml"</span><span style="color: #0000ff;">></span> 
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span> 
<span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span> 
  <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">http-equiv</span><span style="color: #0000ff;">="Content-Type"</span><span style="color: #ff0000;"> content</span><span style="color: #0000ff;">="text/html;charset=UTF-8"</span> <span style="color: #0000ff;">/></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span> 
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span><span style="color: #000000;"> 
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<span style="color: #0000ff;"><</span><span style="color: #800000;">a </span><span style="color: #ff0000;">href</span><span style="color: #0000ff;">="javascript:void(0)"</span><span style="color: #0000ff;">></span>这个不会跳动<span style="color: #0000ff;"></</span><span style="color: #800000;">a</span><span style="color: #0000ff;">></span> 
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<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>