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unary operators : Number of Operands new Data Type Wrapper Objects Object Creation Operator (new) Creating New Objects with Constructors Creating Arrays typeof Undefined The typeof Operator typeof operator : Conversions to Objects typeof operators : Core Language Changes void The void Operator JavaScript in URLs - (negation) : Unary Negation (-)
undefined (value) Undefined Undefined Object Properties converting Conversions to Strings Conversions to Numbers Conversions to Booleans Conversions to Objects
unescape() Reading Cookies unescape()
Unix platforms : Window.open() method browser background color : Document Properties data tainting on : Enabling Data Tainting in Navigator 3.0 window size and : Window Size on Unix Platforms
unnamed functions : The Function() Constructor
untaint() JavaScript Security The taint() and untaint() Functions untaint()
untyped variables : Untyped Variables
URL object URL.hash URL.host URL.hostname URL.href URL.pathname URL.port URL.protocol URL.search URL
URL property Miscellaneous Changes Document Properties Document.URL
URL protocol specifiers javascript: Exploring JavaScript JavaScript URL Execution mailto: Security Holes and Security Hobbles Security Holes and Security Hobbles Security Hobbles in Navigator 3.0
URLs Document.URL String.link() about:cache : Security Holes and Security Hobbles extracting information from : The Location Object javascript: protocol specifier : JavaScript in URLs referral : Document Properties
Usenet, JavaScript newsgroups : Discussion of JavaScript
User-Agent header : Compatibility Through CGI Scripts
userAgent property The Navigator, MimeType, and Plugin Objects Compatibility Through CGI Scripts Navigator.userAgent
users input from : Interact with Document Content interacting with Interact with the User Using the Java System Classes notifying of browser incompatibility : Notifying Users of Old Browsers