Backend databases -- what are the differences?

[Banzaitron <banzaitron@adelphia.net>]

I was wondering what advantages/disadvantages (if any) there are between the
various LDAP backends (BDB, LDBM, LDAP, etc).  I am using BDB, but only
because that is the default with the build files.  I didn't really see
anything in the openldap website documentation that explained the
differences between them, only how to specifiy which one you wanted.  Which
one is being used by most people?

Thanks,
Andy