Over time, our eyes lose their ability to focus to close distances.
It's called presbyopia. Most people start noticing it sometime in their 40's. Until now, the only options were bifocals, trifocals, progressives or wearing multiple pairs of glasses. None of these options are really satisfactory.
Superfocus is a much better solution. A single pair of glasses lets you adjust the focus distance, depending on what you are looking at. Reading, driving, working at the computer -- it's easy to change focus with just one pair of glasses!