Non-destructive software like Lightroom and Aperture was created due to most of the early digital camera models were in their Raw files proprietary. They both produce a Raw file that can be seen by anyone. Like Apple and Adobe they created a seperate file text in which it records a detailed text and a mathematical description of the changes that were made in the image. In this file created it hold information such as color correction, cropping, color saturation, and brightness. And these changes made in your image only apply to the file made such as a TIFF or JPEG. Today most of the non destructive have transformed into having the capabilities photographers need the most such as applying same adjustment to many photos in one operation. In today world many of the wedding photographers use a nondestructive image in their everyday work. Destructive programs such as Adobe Photoshop come to play is when you need to change the pixels in your image.
Destructive editing is that which changes your image’s original pixels. For example, using an adjustment layer to do a desaturation is a non-destructive edit, whilst doing a desaturation with a menu command is a destructive edit. I’ve made a table at the right, which I hope gives you a more complete picture of what I’m saying.
So since filtering the image is destructive, altering forever its pixels, your goal should be, whenever possible, to use filters on either a copy of the image, a copy of the layer, or a Merged Visibles layer. This copy of the image which you use for filtering can then become a Filter Layer. (http://www.myjanee.com/tuts/filter/filter.htm#nondestruct)
After Adobe merged with Macromedia, we now see non-destructive filtering in Photoshop CS3 and higher, too. Unfortunately this so called Smart Filtering is a bit more limited in Photoshop when compared to Fireworks. First of all, you can only apply plugins non-destructively to smart objects in Photoshop, which involves an extra step and limits the plugin effect to the smart object layer. Unlike adjustment layer effects a “smart filter” does not affect any layers below it. The main reason for this limited implementation of non-destruction filtering was speed gain.(http://thepluginsite.com/knowhow/tutorials/introduction/introduction.htm#16)
Now you will be able to use all filter plugins as smart filters on smart objects in Photoshop. However, non-scriptable plugins will not store their filter settings in the smart object.The same will be the case if you exit and restart Photoshop and the plugins does not store the last settings itself.(http://thepluginsite.com/knowhow/tutorials/introduction/introduction.htm#16)