When assigning a character value or embedding a character in a string, certain characters are hard to represent. For those, a backslash (\) starts an "escaped" sequence of characters with special meaning:
\" = double quote inside a string
\\ = backslash
\n = line feed
\t = tab
\' = single quote
\r = carriage return
\f = form feed (new page)
\uxxxx where xxxx are 4 hexadecimal digits = unicode character
Some examples of Unicode characters:
\u00a9 = ©
\u20ac = €
\u2191 = ↑
\u2192 = →