I am quite new to Perl; thus, my question might be naive. I used GDBM_File for working with GDBM database. I wondered that I did not need to install GDBM on my machine. I thought that GDBM module is just an interface connecting to the GDBM core program. However, as it was included in Perl, I thought that it might be included in the Perl Package. I installed CDB_File which is a small Perl Module (few files only). Why I do not need to install CDB core program? How Perl module works as a standalone program? Thanks for your attention!