And google is your friend http://www.utf8-chartable.de/unicode-utf8-table.pl?utf8=0x&unicodeinhtml=hex

C3 BF is utf 8.

Right. So #1 is utf-8. Then #2 is utf-16?

So then why does this:

use utf8;
my $string = "Queensr’che";
no utf8;
[download]

Produce this:

        81      Q       Q
        117     u       u
        101     e       e
        101     e       e
        110     n       n
        115     s       s
        114     r       r
        255     {ff}
        99      c       c
        104     h       h
        101     e       e
 - this is utf8
[download]

When this:

#use utf8;
my $string = "Queensr’che";
#no utf8;
[download]

Produces this:

        81      Q       Q
        117     u       u
        101     e       e
        101     e       e
        110     n       n
        115     s       s
        114     r       r
        195     
       191     
       99      c       c
        104     h       h
        101     e       e
 - this is NOT utf8
[download]

If the two bytes are "there", why is "use utf8" yielding a dec 255 for the "’" which is not valid utf8?

"The first 128 characters (US-ASCII) need one byte. The next 1,920 characters need two bytes to encode." - http://en.wikipedia.org/wiki/UTF-8

Right. So #1 is utf-8. Then #2 is utf-16?

No, #2 is ISO-8859-1, which is also known as Latin 1. As it happens, it's also Windows-1252, which today is really a quasi-superset of ISO-8859-1. Neither ISO-8859-1 nor Windows-1252 are Unicode at all, so #2 is not in any Unicode character encoding scheme such as UTF-16.

The character encodings ISO-8859-1 (Latin 1) and Windows-1252 are often referred to as "legacy encodings," especially vis-ą-vis Unicode.