Flash is not just for fancy effects. Flash is first and foremost, an animation software. It is also very versatile.
Flash with actionscript can do almost everything you need in a website. It can do what PHP and Javascript can do and in most cases look much slicker. What I like about Flash is that you cannot peek at the code easily like other client side technologies like Javascript.
Flash has changed throughout the years. It was started by Macromedia and was later sold to Adobe. Lately in AS3, Flash has become an Object-oriented programming (OOP) language to make it more appealing to programmers but it still accept the old style scripting (AS2).
Flash is no longer popular because of the vulnerabilities and browsers does not recommend using it. Adobe will kill it by 2020. I have stopped using and writting about it. Flash has been replaced by HTML5 and Javascript.
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