Print data, followed by a newline, to the last client connected to a server. Prints numbers as a sequence of digits, each an ASCII character (e.g. the number 123 is sent as the three characters '1', '2', '3').
// SYNTAX server.println(); server.println(data); server.println(data, BASE) ;
data(optional): the data to print (char, byte, int, long, or string)
BASE(optional): the base in which to print numbers: BIN for binary (base 2), DEC for decimal (base 10), OCT for octal (base 8), HEX for hexadecimal (base 16).