"?" in a diamond appears in my webpage. What does it mean?

I have attached a picture of it. I'm using a tracking script. If I don't use it, it's ok. Anyone can help?

 

Its probably a character set issue. Either the wrong type of headers are sent or some fonts may be missing!

 

You might have an open php tag somewhere that has not been closed properly; look in the code for <? and > somewhere; change > to ?>

or it could be < and a ?>

 

its a problem for encoding, basically the browser does not know how to translate the character,

 

It's a charset issue, I can't really see it well but here are some hints

If you just finished a design or something to a dynamic script

1) Ensure that the script charset is UTF-8
2) Ensure that the design's charset is UTF-8 (both have to be the same)

The browser sends/read the encoding according to the meta charset set. The script handles the data according to the charset set. If one is ISO-8889-1 and another is UTF-8 it will make those errors.

 

Thanks for replying guys. It appears the charset stuff is working. I haven't had any problem with it though. Thanks.