Following are the implicit EL (Expression Language) objects:-

Page Context: The context for the JSP page.

Provides access to various objects for instance:-

servletContext: The context for the JSP page's servlet and any web components contained in the same application.

session: The session object for the client.

request: The request triggering the execution of the JSP page.

response: The response returned by the JSP page. See Constructing Responses.

In addition, several implicit objects are available that allow easy access to the following objects:

param: Maps a request parameter name to a single value

paramValues: Maps a request parameter name to an array of values

header: Maps a request header name to a single value

header Values: Maps a request header name to an array of values

cookie: Maps a cookie name to a single cookie

initParam: Maps a context initialization parameter name to a single value

Finally, there are objects that allow access to the various scoped variables described in Using Scope Objects.

page Scope: Maps page-scoped variable names to their values

request Scope: Maps request-scoped variable names to their values

session Scope: Maps session-scoped variable names to their values

application Scope: Maps application-scoped variable names to their values

For instance the below snippet will indentify the browser used by the client.

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