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Type coercion
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UDP (User Datagram Protocol)
UI
Undefined
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URL
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World Wide Web
Wrapper
XForms
Deprecated
XHTML
XInclude
XLink
XML
XMLHttpRequest (XHR)
XPath
XQuery
XSLT
Zstandard compression
Instance
An
object
created by a
constructor
is an instance of that constructor.
See also
Instance
on Wikipedia
In this article
See also