import flash.system.Capabilities;

trace("Capabilities.avHardwareDisable: "+Capabilities.avHardwareDisable);
trace("Capabilities.hasAccessibility: "+Capabilities.hasAccessibility);
trace("Capabilities.hasAudio: "+Capabilities.hasAudio);
trace("Capabilities.hasAudioEncoder: "+Capabilities.hasAudioEncoder);
trace("Capabilities.hasEmbeddedVideo: "+Capabilities.hasEmbeddedVideo);
trace("Capabilities.hasMP3: "+Capabilities.hasMP3);
trace("Capabilities.hasPrinting: "+Capabilities.hasPrinting);
trace("Capabilities.hasScreenBroadcast: "+Capabilities.hasScreenBroadcast);
trace("Capabilities.hasScreenPlayback: "+Capabilities.hasScreenPlayback);
trace("Capabilities.hasStreamingAudio: "+Capabilities.hasStreamingAudio);
trace("Capabilities.hasVideoEncoder: "+Capabilities.hasVideoEncoder);
trace("Capabilities.isDebugger: "+Capabilities.isDebugger);
trace("Capabilities.language: "+Capabilities.language);
trace("Capabilities.localFileReadDisable: "+Capabilities.localFileReadDisable);
trace("Capabilities.manufacturer: "+Capabilities.manufacturer);
trace("Capabilities.os: "+Capabilities.os);
trace("Capabilities.pixelAspectRatio: "+Capabilities.pixelAspectRatio);
trace("Capabilities.playerType: "+Capabilities.playerType);
trace("Capabilities.screenColor: "+Capabilities.screenColor);
trace("Capabilities.screenDPI: "+Capabilities.screenDPI);
trace("Capabilities.screenResolutionX: "+Capabilities.screenResolutionX);
trace("Capabilities.screenResolutionY: "+Capabilities.screenResolutionY);
trace("Capabilities.serverString: "+Capabilities.serverString);
trace("Capabilities.version: "+Capabilities.version);

// OUTPUT ...
//Capabilities.avHardwareDisable: false
//Capabilities.hasAccessibility: true
//Capabilities.hasAudio: true
//Capabilities.hasAudioEncoder: true
//Capabilities.hasEmbeddedVideo: true
//Capabilities.hasMP3: true
//Capabilities.hasPrinting: true
//Capabilities.hasScreenBroadcast: false
//Capabilities.hasScreenPlayback: false
//Capabilities.hasStreamingAudio: true
//Capabilities.hasVideoEncoder: true
//Capabilities.isDebugger: true
//Capabilities.language: en
//Capabilities.localFileReadDisable: false
//Capabilities.manufacturer: Adobe Windows
//Capabilities.os: Windows XP
//Capabilities.pixelAspectRatio: 1
//Capabilities.playerType: External
//Capabilities.screenColor: color
//Capabilities.screenDPI: 72
//Capabilities.screenResolutionX: 1280
//Capabilities.screenResolutionY: 1024
//Capabilities.serverString: A=t&SA=t&SV=t&EV=t&MP3=t&AE=t&VE=t&ACC=t&PR=t&SP=f&SB=f&DEB=t&V=WIN%2010%2C0%2C22%2C91&M=Adobe%20Windows&R=1280x1024&DP=72&COL=color&AR=1.0&OS=Windows%20XP&L=en&IME=t&PT=External&AVD=f&LFD=f&WD=f&TLS=t&ML=5.1
//Capabilities.version: WIN 10,0,22,91

http://livedocs.adobe.com/flash/9.0/ActionScriptLangRefV3/flash/system/Capabilities.html

AS3 flash.system.Capabilities Properties

ActionScript 3