Those who wants to create his own photo gallery or photo gallery for his client can use Highslide JS. It is a very nice javascript thumbnail viewer by Torstein Honsi.

I created a gallery for my client fairapparels.

What you have to do is simply call the highslide.js in the head section of your html. There are some Style Sheet which u can put in the style section or cal call from external CSS file. Then Write the code like below (as for example)

<a href="large-image.jpg" class="highslide"
onclick="return hs.expand(this)">
<img src="thumbnail.jpg"
alt="Highslide JS" title="Click to enlarge"
height="100" width="100" />
</a>

OR

<a href="showimage.php?src=images/large-image.jpg"
class="highslide"
onclick="return hs.expand(this, {
src: 'images/large-image.jpg' } )">
<img src="thumbnail.jpg"
alt="Highslide JS" title="Click to enlarge"
height="100" width="100" />
</a>

You can download Highslide JS from http://vikjavev.no/highslide/