Scripting Languages

Some hypertext systems offer a small programming languages to associate buttons with programs rather than fixed documents. Guide, Hyperties, Intermedia and Multicard are examples of such systems.

Apart from a scripting language, some systems provide the possibility of executing external programs, possibly delivering a document or node as a result.

A good example of a system offering both is HyperCard, with its HyperTalk language. Hypertalk is a complete programming language. It is interpreted, making execution of long scripts quite slow. It also contains an open command to launch external applications.

The World Wide Web provides no scripting language, but its HTTP servers may execute external programs. Different WWW browsers offer different scripting languages of their own. Netscape created Javascript, a scripting language with a syntax vagualy similar to that of the Java programming language. Microsoft introduced VBscript, with a syntax similar to Visual Basic. Microsoft's Internet Explorer supports part of Javascript, but Netscape Navigator does not support VBscript.

There is no emerging standard scripting language for hypermedia applications. Such a standard however is required in order to move applications between hypermedia systems. One of the reasons why the CD-I platform did not catch on with other manufacturers or the PC world is that it has no high-level scripting language. All CD-I programs are stored in 68000 machine code. Putting 68000 code on the CD-ROM makes it difficult or impossible to use CD-I hyperdocuments on other systems than CD-I players or computers with a cpu from the Motorola 68000 family.