I'm using PhotoShop CS to edit some pictures in order to create wallpapers at 1024x768 pixels.
I used to have the notion that more pixels per inch mean a better resolution of a particular image. However I observe there are bmp and jpg files that have different pixels per inch, some have 72, other have 200 or 300. By using PhotoShop and loading and saving the same files while increasing the number of pixels per inch, I don't see any difference in picture quality.
I even saw pictures at the same size (1024x768) at 72 dots per inch having better quality than some others that have 300 dots per inch.
Please any graphics expert explain this 'pixels per inch' definition before I'm getting lost?