Hard Riddle: Joe and Sally were sitting in their family room one night. While Joe was watching T.V, his wife Sally was reading. All of a sudden the power went out and Joe decided to go to bed, but Sally kept on reading. With no use of artificial light, Sally kept on reading. How?
In order to find or understand the answer of this riddle you need to know what Braille is. Braille is a system of printing for blind people, in which each letter is represented as a raised pattern that can be read by touching it with the fingers.
Therefore, when the power goes out while Joe decides to go to bed Sally can stay awake and keep on reading her book and she did not need any sort of artificial light to read a book.
The answer of this riddle is that Sally is blind, and she is reading a book by Braille.