Codes

Geeky note: Do you sometimes see text that does not display correctly, like "&qte" or "�£10"? Do you ever see text that does not flow correctly? It is crazy that after all these years, the codes used for characters are still not standardized. Actually they are but some programs do not follow the standard. The characters you see on your screen are really numbers.
http://www.tutorialspoint.com/html/ascii_table_lookup.htm
They date to the time of teletype machines. The number 65 is shown as "A". Yet the new line code is different on different kinds of computers. On Windows it is 10, 13, meaning "linefeed, carriage return". That means, go down a line, and go back to the beginning of the line. On Macs, they just use 13, and on Unix, they just use 10.
There are several sets of characters for the numbers from 128 to 255, but since they differ, in web pages they use special code sequences:
http://www.webmonkey.com/reference/Special_Characters