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# Server-side Code

Everything that happens within your server computer is referred to as server-side processing. When your application needs to interact with your server (for example, to load or save data), it makes a client-side request (from the browser) across the network using a remote procedure call (RPC). While processing an RPC, your server is executing server-side code.
Tip
GWT doesn't meddle with your ability to run Java bytecode on your server whatsoever. Server-side code doesn't need to be translatable, so you're free to use any Java library you find useful.