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Macromedia Flash
Macromedia Flash is a vector graphics based graphics animation program.
The resulting files, sometimes called "flash files", may be included in a web page to view in a web browser, or they may be played on a standalone player.
Flash uses Anti-aliasing.
".fla" files are like the source code. They can be edited with Flash software. "fla" is pronounced "flaw".
".swf" files are completed, published files that cannot be edited. "swf" is pronounced "swiff".
Later versions of Flash can also create files in a variety of static or animated formats.
The Macromedia Flash file format has several advantages over "regular" HTML pages that make it an extremely popular option for professional web site creation:
- Like PostScript and PDF, Flash allows exact specification of where the various page elements are, and so it gives the designer a great degree of control over how the user interface looks. It is much more difficult to do the same with HTML and CSS.
- Flash uses vector graphics; they may translate into small file sizes which take less bandwidth to transmit than bitmaps do.
- The Flash file format has been opened by Macromedia, and compatible third-party tools exist.
- Flash's file format is not platform-dependent; players exist on Microsoft Windows, Mac OS, Linux and various UNIX systems.
- Flash allows the embedding of images ,sounds ,movies and simple HTML files. These abilities make it a good multimedia platform.
- Flash's embedded ActionScript language (an application of the ECMAScript programming language) allows the creation of simple fill-in-the-blank forms.
In FlashMX, the ActionScript language has been extended and can be used to create extensive event driven GUI's. Macromedia has stated their intention of moving Flash away from the simple animations of web ad banners and move toward true application development.
There are also some disadvantages to Flash:
- Viewer plugins don't exist for all systems, and they're not installed on all computers that can run them.
- Though the flash file format is ostensibly "open", it is still controlled by Macromedia and not based upon a truly open standard such as SVG, which reduces the incentive for non-commercial software to support it. The Macromedia player can not be shipped as part of a pure open source operating system.
- Due to Flash's graphical nature, it does not degrade gracefully to disabled users. It is possible to overcome this only by providing alternative content (for example in HTML). See also accessibility[?].
- Flash does not support internationalization thoroughly.
- Flash demands significant CPU power to display, as it uses a very high degree of graphic abstraction that many video cards are not able to accelerate.
- The browser plug-in may store and retrieve information on the user's computer, acting much like HTTP cookies and with similar advantages and disadvantages.
- The plug-in has had security flaws which may open up a computer to remote attack (e.g., see [1] (http://www.macromedia.com/v1/handlers/index.cfm?ID=23569) and [2] (http://www.theregister.co.uk/content/55/28645.html) for a December 2002 problem).
In Flash MX, the latest release, several of the disadvantages have been addressed. See http://www.useit.com/alertbox/20001029.html for a discussion of Flash and usability.
See also: