Different ways of customizing behavior with configuration
Software is a combination of code and configuration. The code is the core and configuration is the personality that lets the software operate in a specific environment or lets the operator adjust the way the software operates within certain parameters. Good software provides various ways of customizing its behavior without requiring a code/test cycle. This customization is done through some type of configuration mechanism. Customization and configuration can be "baked in", set on startup, or updated while the system runs. Different techniques work better at different times
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