Today's useless fact - Why is normal vision referred to as 20/20?
Visual acuity is expressed as a fraction. The top number refers to the distance you stand from the chart. This is usually 20 feet. The bottom number indicates the distance at which a person with normal eyesight could correctly read the line with the smallest letters. Normal vision is considered 20/20. If your vision is 20/40, the line you correctly read at 20 feet could be read by a person with normal vision at 40 feet.
Of course, just because 20/20 vision is normal doesn't mean it's perfect. A small percentage of the population is blessed with vision better than 20/20, and just recently researchers unveiled corrective lens that offered vision closer to 20/10.
And for a smile.... A photo shop got a reprint order for a picture of a man milking a cow. The man sat behind the cow, and all that was visible were his feet. A scrawled note read, "This is my only photo of my grandfather. Please remove the cow so I can see what Grandpa looked like."
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