Nonfunctional requirements cover other features that the application must have besides the ability to perform its functions. For example, they may include the ability to interface with legacy systems, performance criteria (such as a specific number of transactions a second), and user interface constraints, such as that the application must run on a browser.
The following are the nonfunctional requirements for the Java(TM) Client Sample Application:
The sample application can be executed by running the client and the server sides of the application either on two different machines, or on the same machine but using two different Java Virtual Machines.