syncronizing databases?

Hi All,

If this is the wrong list to post this question to forgive me, correct
me and I'll be out of your hair.

Here's my question:

I have two identical databases setup on separate servers and I'm
looking for ideas on how to keep the data syncronized.  I'm wondering if
there is some feature or function of PostgresQL that will compair tables
directly or do I need to create my own some how.  I'm running PostgresQL
v7.1 on RedHat 7.2 servers and have a couple of users that will be
maintaining data and need to find a simple method of updating one db
based on the other one.  One of our servers is in production, serving
our website, the other is a backup server.  I'd like to have the users
only need to enter data once, preferably on the backup server and then
either periodically or on demand have the two servers sync.  Make
sense?

Any suggestions are greatly appreciated.

Thanks in advance,
Linn