[miraceti@centenum blast]$ 
[miraceti@centenum blast]$ which perl
/usr/bin/perl
[miraceti@centenum blast]$ cat hello.pl
#!/usr/bin/perl -W

print "Hello, World!\n";


[miraceti@centenum blast]$ ./hello.pl
[miraceti@centenum blast]$ perl hello.pl
Hello, World!
[miraceti@centenum blast]$