Index[A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Z] UIEvent interface 2nd 3rd 4th initUIEvent( ) method unary operators 2nd associativity new typeof void unassigned vs. undefined variables unbind( ) method undeclared variables undefined datatype 2nd identity comparisons undefined elements in array literals undefined property undefined values conversion to Java generating with void operator properties unassigned vs. _ (underscore) in function names in identifiers prefixing private symbols unescape( ) function 2nd Unicode in identifiers in string literals keypress events represented as hexadecimal, escape sequences whitespace characters, matching in regular expressions unit values, specifying for style properties universal (UTC) time 2nd 3rd Date object methods for difference from local time unnamed functions, embedding in programs as literal data values unobtrusive JavaScript 2nd DOM Scripting Task Force, JavaScript Manifesto image rollovers unshift( ) method (Array) untyped languages updating loop variables URIError object URL property Document object HTMLDocument object URLs Ajax applications and assigning to location property currently displayed document JavaScript in 2nd bookmarks embedding JavaScript in HTML execution of scripts Location object and XMLHttpRequest object and useMap property user scripting userAgent property (Navigator) 2nd userData persistence behavior sharing persistent data storage limits storing hierarchical data |