String Data Type
There are two kinds of strings: variable-length and fixed-length strings.
A variable-length string can contain up to approximately 2 billion (2^31) characters.
A fixed-length string can contain 1 to approximately 64K (2^16) characters.
The codes for String characters range from 0–255. The first 128 characters (0–127) of the character set correspond to the letters and symbols on a standard U.S. keyboard. These first 128 characters are the same as those defined by the ASCII character set. The second 128 characters (128–255) represent special characters, such as letters in international alphabets, accents, currency symbols, and fractions. The type-declaration character for String is the dollar sign ($).