ActionScript is a scripting language used for RIAs, mobiles applications, web applications, etc.
ActionScript is a scripting language used for RIAs, mobiles applications, web applications, etc. which was initially developed by Macromedia and then acquired by Adobe. It targets to compile for Flash player runtime which can be deployed in various platforms including mobiles.
The language itself is open-source in that its specification is offered free of charge and both an open source compiler (as part of Apache Flex) and open source virtual machine (Mozilla Tamarin) are available.