Are there algorithms for increasing resolution of an image?

algorithmimageimage-scalingresolution

Are there any algorithms or tools that can increase the resolution of an image – besides just a simple zoom that makes each individual pixel in the image a little larger?

I realize that such an algorithm would have to invent pixels that don't really exist in the original image, but I figured there might be some algorithm that could intelligently figure out what pixels to add to the image to increase its resolution.

Best Solution

Interpolation: Image Scaling