You can name your functions anything you want. I chose to name mine MsgBox, but I could have named it Kalamazu or something else.

A function is typed like this:

function MyFunction (variable) {

(stuff you want to do with the variable)

This animation shows how a number can be passed to the variable "data" and then used in a function written for that variable.

The variable can be a number, a piece of text, or a date.
The curly brackets { } define the beginning and end of the function.

The alert command will create an message box displaying a piece of text or a number.

Alert("Hello World") will display Hello World in the box.

Alert(SomeText) will assume that SomeText is a variable, and will display whatever value it contains. Notice that "Hello World" was in quotes and SomeText was not. If I put these two lines together:

SomeText="My Three Sons"
Alert(SomeText)

then My Three Sons will be displayed in the message box.

<SCRIPT LANGUAGE="JavaScript">
< !-- Beginning of JavaScript -

function MsgBox (textstring) {
alert (textstring) }

// - End of JavaScript - -->
</SCRIPT>

How do I put it to work?