Report Manager Server is a multithread service/application that works over TCP/IP protocol. It allows any number of client machines to execute reports obtaining ready to print report metafiles.
You must start the server application (available also as a service) in the server machine, in the server machine you should have database connectivity software so the reports can execute on it.
The database server can be any machine accesible by the report server machine, so you can distribute the work of generating reports, for example the report client can be a Internet enabled connection requesting a report to a far network (also connected to Internet) server, the server generates the report requesting process intensive querys to a high performance database server, after the calculation of the report is done, the server sends the result to the report client.
The report client application can request information about parameters and also alter them before executing the report.
The server and the client are optimized to use very little bandwith.
You can install the report server in a linux machine and execute report client in MS Windows machines or vice-versa.
Configuration
Report Manager server runs using port 3060,you can run the server as an application and see the report configuration and log files. You can alter all settings using repserverconfig application except the port (you can alter it modifying the configuration file).
By default there is only one user named Admin and without password. You can assign a password to Admin user, and add other users. The Admin user is the only one with privileges to add Report Server aliases.
A report alias is a name and a path that points to a directory that can contain reports and directories containing reports so a report tree is generated using the directory structure, the reports are stored in the server and the report tree is send to the report client.
Other considerations
When you design reports for use with report server you must configure them to be thread safe, that is make sure your driver supports multithread (as far as I know all drivers supports this) and your database connection string is thread safe, for example to access Interbase/Firebird databases provide the always the hostname (or write localhost), so the access method to the database is thread safe (local access method is not thread safe).
See also how to install the server.