The rest of the program has been divided into three separate packages: {@link net.sf.freecol.client client}, {@link net.sf.freecol.common common} and {@link net.sf.freecol.server server}.
You might have noticed a fourth package named
{@link net.sf.freecol.metaserver metaserver}, but this is a separate
program. The metaserver is running on meta.freecol.org:3540
in order to maintain a central list of public servers.
The client and the server are really two different programs, even though it is possible to start the server from the client GUI, and all interaction between the client and the server, after the creation of the server, should be done by communicating through the network.
Both the clients and the server has a game model, but only the server has the complete game model containing all the information. The client model only contains the information being visible to the player using the client.
One important point here is: You will need to update all the clients' models as well as the server model if you want perform an action (like building a colony, moving a unit etc).
Read more at:
Overview of the client/server-architecture
common package contains everything being shared between
the client and the server. One of these things is the
{@link net.sf.freecol.common.model game model} which is best described as
being a model of the imaginary world we are creating.
The model should only contain the information needed to model the imaginary world. That is; it should not contain information on how the map should be displayed etc.