what is flash?

I am lerarning photoshop & illustrator,i also intersted on flash,but i don't know about flash cheractaristic & what type of work is do by using flash?:(

Have a look on how Adobe itself describes what is the purpose of Flash : http://www.adobe.com/products/flash.html

can i get some kinds of resource from this site?:o

What kind of resources you need? Tutorials? Books? Code samples? You want to focus on the animation part of Flash or to learn AS3 (the language behind)?