Monthly Archives: April 2014
272.WHAT IS THE BRAILLE SYSTEM?
If you were unfortunate enough to be blind, one of the greatest losses you would feel would be not being able to read. Just think how important the ability to read books is to you. Well, people realized this a long time ago and tried to find methods for enabling blind people to read.
For example, as far back as 1517 there was a system of engraving letters on blocks of wood so blind people could make them out with their fingers. A person’s fingertips are very sensitive and a blind person can “read” with his fingers. A great many other systems were worked out over the years, using raised lines for the letters. But they all presented one big problem: while blind people could learn to read in this way, they couldn’t easily write this way because they couldn’t see how to form the letters.
271.WHAT IS HIEROGLYPHIC WRITING?
The word “hieroglyphs” means “sacred carvings.” Actually, it is not an accurate name for the ancient writing of the Egyptians. It came about because when the early Greeks first saw these writings, they believed they were made by priests for sacred purposes.
But Egyptian hieroglyphics is really one of the oldest known systems of writing. Some of the inscriptions go back to before 3000 B.C., and hieroglyphics continued to be the written language of Egypt for more than 3000 years.
270.WHAT IS CRYPTOGRAPHY?
Suppose you and your friends wanted to set up a system of sending secret messages to each other You might say, “Instead of using letters, let’s use numbers.” Each number will stand for a certain letter of the alphabet.
You would then have a code. Cryptography is writing using a secret code. Sometimes the word “cipher” is used instead of code. Did you know that Julius Caesar used a cipher to keep his message secret from enemy eyes? In modern times, ciphers and codes are used by both government and business for important and secret messages.
