Upgrade in same major version

Hello,

I'm doing an upgrade from 8.2.4 to 8.2.10.  The documentation says,
"When you update between compatible versions, you can simply replace
the executables and reuse the data directory on disk."  I guess I
don't quite understand what this means.  Replace them by running some
parts of the installation process?  Replace them by copying them.
Are you talking about those files that usually reside in /usr/local/
pgsql/bin and include psql and pg_ctl?

I know these may seem like dumb questions to those of you who are old
hands at this.  I'd be glad to read more documentation if there is
some that is more explicit than what I quoted above.

Thanks so much,

Carol