Shell Programming and Scripting

Hi,
I want to know all the keywords in perl as well as their usage. plz provide if u have any URL regarding this.
In my perl script first 2 lines are
1)use DBI;
2)require "hello.pl";
what is the use these two statements.
i thought the second one may be like include .
Thanks in advance.
Sarwan

Both "use" and "require" means to include some external modules/scripts. The major difference being "use" is a "compile-time" construct, and missing module will cause a run-time error with "require", but a compile-time error with "use". So "use" will help you locate missing modules earlier compared with "require" before the script starts execution.

Also, "use" is mostly used to include reusable, object-oriented modules; while "require" are frequently used to include external scripts.

For keywords, you will see all of them defined in the Perl set of manpages everywhere. There are simply too many to be listed