In XML (including XHTML), the following are all equivalent:

<foo></foo>
<foo />
<foo/>

I think this is true for all tags except the XML declaration and the DOCTYPE, which are special. There may be other special tags, but if so I am not aware of them. They would have to start with a non-alphanumeric character (e.g., a ! like the doctype or a ? like the XML declaration) in order to prevent their being parsed as regular XML tags.

The third form is the most minimalist, but it creates problems for certain legacy browsers, so one of the first two approaches is recommended. Which one depends on whom you ask. They are equivalent if the program parsing them is compliant. 

for(unpack("C*",'GGGG?GGGG?O__\?WccW?{GCw?Wcc{?Wcc~?Wcc{?~cc'
.'W?')){$j=$_-63;++$a;for$p(0..7){$h[$p][$a]=$j%2;$j/=2}}for$
p(0..7){for$a(1..45){$_=($h[$p-1][$a])?'#':' ';print}print$/}

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In reply to Re: br tag in CGI.pm V2.91 by jonadab
in thread br tag in CGI.pm V2.91 by cLive ;-)

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