Filters can perform many different types of functions.
* Authentication-Blocking requests based on user identity.
* Logging and auditing-Tracking users of a web application.
* Image conversion-Scaling maps, and so on.
* Data compression-Making downloads smaller.
* Localization-Targeting the request and response to a particular locale.
* XSL/T transformations of XML content-Targeting web application
responses to more that one type of client.
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