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The Math Object Random Changes To keep people coming back it is sometimes nice to have your index page different each time. For instance : On my personal pages Geoff's World I play a different midi randomly chosen each time the page is reloaded. To do this it is a simple matter of using JavaScript 'random' to choose a number and then accessing an array with that number. There are a couple of things that we must understand first. JavaScript random will give you a number between 0 and 1 choice=Math.random(); Not much good to us like that but if we multiply it by the number of choices we need it begins to make sense choice=Math.random()* 4; Last thing is to make the number an integer getting rid of all that superfluous stuff after the decimal point For this we use 'Math.round' choice=Math.round(Math.random()* 4); What we have done is combine three steps in one statement which makes sense. It could have been written choice = Math.random; choice = choice * 4; choice = Math.round (choice ); We now have a number between 0 and 4 ( Remember this is a computer language so you have 5 choices ) We can access an array with the answer to alter the experience on each reload. Recapping : Here is the script <Script Language="JavaScript"> <!-- choice = Math.round(Math.random() * 4 ); message = new Array ( 'Hello' , 'Hi' , 'Aloha' , 'Bon Jour' , 'Ciao'); document.write(message[choice]) //--> </Script> Next : Interact with HTML Home