From http://www.w3schools.com (Copyright Refsnes Data)

Flash How To..

Who can View Flash?

In September 2000, NPD Research, the parent company of MediaMetrix, conducted a study to determine what percentage of Web browsers have Flash preinstalled. The results show that 96.4% of Web users can experience Macromedia Flash content without having to download and install a player.

If you do not have the Shockwave Player installed you can download it for free from Adobe's site.

Who can Create Flash Movies?

To create your own Flash movies you need to buy a Flash program.

The latest version from Adobe is Adobe Flash Lite (or Flash CS3 Pro).

If you do not have a Flash program, you can download a 30 days free trial version of Flash from Adobe.

Where to Start?

After you have installed Flash, you should go through the lessons that are included in the program. Start Adobe Flash, click Help in the menu and choose Lessons. These lessons will teach you the basics of Flash.