Perl is a powerful, efficient *general purpose* programming language. So you can write system administration tasks, games, applications, whatever with perl. You can sort of do this with PHP, but perhaps its a little trickier. You can't do this with JSP or ASP. You can only write stuff for the web.
PHP is OK for developing web stuff. And at least it is open source. Perl can do much of what php can through mod_perl or cgi, is more difficult to learn, but can also do many general programming tasks that php can't. It also has an enormous centralized library of 'modules', CPAN (http://www.cpan.org
)that php has yet to achieve.
JSP is a sun owned and rather verbose subset of java which can be used to develop websites. Its more suited to large applications. Perl is less verbose, and suitable for small or large websites.
ASP is a proprietary, microsoft specific extension to their infamously insecure IIS webserver, used by only around a quarter of active websites (http://news.netcraft.com/archives/20...er_survey.html
As to people still working with perl, the short answer is yes. See http://www.dedasys.com/articles/lang...opularity.html
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