A package typically is a bundle of files that together allow you to perform a task.
Let's have a look at a small rpm package file, distcc-server-3.1-1.i386.rpm. It is available from the internet and installs a distributed C compiler environment. The name consists of several parts:
distcc-server: the name of the package
3.1-1: 3.1 is the version, -1 means this is the first version of the packager.
i386: This package is for the i386 processor family. "noarch" would mean it is not architecture dependant.
Let's look what files are in this package:
# rpm -qpl distcc-server-3.1-1.i386.rpm /etc/default /etc/default/distcc /etc/distcc /etc/distcc/clients.allow /etc/distcc/commands.allow.sh /etc/init.d/distcc /etc/logrotate.d /etc/logrotate.d/distcc /etc/xinetd.d /etc/xinetd.d/distcc /usr/bin/distccd /usr/share/man/man1/distccd.1.gz