programs that interact with the user and control the browser. Today's lesson
In particular, the information for today's lesson comes primarily from
pages 1 through 23 in this book.
INDEX CARD #J1:
enabling Web authors to spice up their sites with dynamic content.
has been embedded in Netscape Navigator, Internet Explorer, and other
What is a scripting language?
A script is a list of commands that can be executed without user interaction.
A scripting language is a simple programming language to write scripts.
Supposedly, scripting languages are "programming languages for non-programmers."
What does object-oriented mean?
The term object-oriented describes a system that
deals primarily with different types of objects, and where the actions you can
take depend on what type of object you are manipulating.
language from Sun Microsystems. Originally,
last minute as a marketing ploy.
Are there other programming languages that can be embedded within
perform math computation; work with dates and times;
compute sales tax on an on-line order
control document appearance and content; put current date and time in a document; display different content on different platforms
control the browser; pop up dialog boxes to display messages and get user input;
open and close new browser windows; download and display contents
of any URL in any window or frame
interact with HTML forms; read and write values in forms; verify that form input is correct
before sending it to be processed by a CGI script on the server side
interact with the user; have different things happen based on what the user does; for example, display a special message in the status line when the mouse hits a certain link
read and write client state with cookies; A "cookie" is a small amount of data that is stored on the client's
machine. Cookies are transmitted to and from the server to give information
programs can read and write cookie values.
can't draw graphics; However, it can dynamically generate images, tables, frames, forms, fonts, etc. for the browser to display.
can't read or write files; This is for security reasons. Would you want any old program
from an unknown source running on your computer and messing with
doesn't support networking. (A network is simply
can download arbitrary URLs and send the contents of HTML forms to CGI scripts, email addresses,
and Usenet newsgroups.
The following example illustrates many of the features of a typical
NOTE: In mathematics, 5! is read as "five factorial" and is