Abhi I thought this is the fastest method
It can be, but there again, if the site is down, or experiencing a lot of traffic, then by definition, your site will also be slow.
Abhi This part, I didn't follow.
Yes, this is a well known fact. It's for the same reason that developers used sprites years ago as downloading one image containing hundreds of sprites was much more efficient than downloading hundreds of individual images. With sprites, you just needed to specify the coordinates on the image from where you wanted to locate that particular sprite - here's an example https://stackoverflow.com/questions/1452961/how-to-find-pixel-position-of-image-from-sprite-image