SQL Guide : Database concepts : Client-server architecture
  
Client-server architecture
solidDB® uses the client-server model. In a client-server model, a single “server” may process requests from 1 or more “clients”. This is quite similar to the way that a restaurant works — a single waiter and cook may handle requests from many customers.
In a client-server database model, the server is a specialized computer program that knows how to store and retrieve data efficiently. The server typically accepts four basic types of requests:
Insert a new piece of information
Update an existing piece of information
Retrieve an existing piece of information
Delete an existing piece of information
The server can store almost any type of data, but generally does not know the “meaning” of the data. The server typically knows little or nothing about “business issues”, such as accounting, inventory, and so on. It does not know whether a particular piece of information is an inventory record, a description of a bank deposit, or a digitized copy of the song “American Pie”.
The “clients” are responsible for knowing something about the particular business issues and about the “meaning” of the data. For example, we might write a client program that knows something about accounting. The client program might know how to calculate interest on late payments, for example. Or, the client might recognize that a particular piece of data is a song, and might convert the digital data to analog audio output.
It is possible to write a single program that does both the “client” and the “server” part of the work. A program that reads digitized music and plays it could also store that data to disk and look it up on request. However, it is not very efficient for every company to write its own data storage and retrieval routines. It is usually more efficient to buy an off-the-shelf data storage solution that is general enough to meet your needs, yet has relatively high performance.
See also
Database concepts