Difference between flash and flex

can anybody tell me what is the difference bet ween flex and flash...according 
to my knowledge using flash you build .swf file which contains some scripting 
(actionscripting) and using flex also you can include actionscripting. i am not

able to understand the difference between flash and flex....Please help

Here's my perspective as a Flex engineer.

 Flash was originally a tool for graphic designers, to which we've added 
developer (coder) features. The Flash authoring tool has lots of drawing tools 
for designers to create graphics, a Stage for arranging graphics spatially, and

a timeline for making them change over time. Developers can add interactivity 
by writing ActionScript code. The result is a SWF file to be played by the 
Flash Player, either in a browser or not. People tend to use Flash to create 
web ads, games, websites where graphic design is paramount, etc. Flash also 
offers some components like CheckBox, ComboBox, List, etc. that you can 
assemble to create applications.

 Flex is more oriented towards developers, especially those who are used to 
using HTML, CSS, and JavaScript and less towards designers. It is used 
primarily to create business-type applications. Flex provides an application 
"framework" which provides the components you need to create complex 
applications. Flex's set of components is much more extensive than those in 
Flash. You write Flex applications in a combination of ActionScript and a 
HTML-like language caled MXML. You compile these to produce as SWF. The 
FlexBuilder authoring tool lets you lay out your application visually as well 
as write and debug ActionScript and MXML, but it doesn't provide tools for 
creating graphics. There is also a Flex Data Services server which can do 
things like synchronize data across many users.

 Does that help you to figure out which one would better fit your needs?