programming-for-dummies

486
The Structure of a JavaScript Program
Despite its name, JavaScript is a completely different programming language
from Java, although both languages borrow heavily from the C++ syntax that
includes the use of curly brackets and semicolons ending each statement.
On the Mac OS X, Dashboard widgets, which are tiny programs that pop up
on the screen, are made with JavaScript code.
The Structure of a JavaScript Program
At the simplest level, a JavaScript program can consist of one or more commands,
such as
document.writeln(“This is a simple JavaScript program.”);
The and tags define the beginning and ending of a
JavaScript program. The first tag identifies the scripting language
used, which in this case is always JavaScript. Sandwiched in between the
two tags are the actual JavaScript commands.
However, it’s more common to divide a JavaScript program into functions
with each function acting like a separate building block. For example, a
simple JavaScript program might look like this:
The onLoad command tells your computer when to run a particular function.
As an alternative to storing JavaScript code directly in the HTML code of a
Web page, you can store JavaScript programs in separate files. Then you