This is a 32bit version of the SWF handler installed by the Adobe Flash application. It's installed in your browser's plug-ins folder and provides Flash functionality for websites and installed applications who use this technology. If you remove the file, the browser's behavior will change by giving errors related to Adobe Flash or this DLL. It's advised to keep the file installed. If by some means it was infected with a virus, run a cleaning operation using your antivirus then download and install a new version of Adobe Flash.
Note: Make sure to uncheck the McAfee offer when installing the software from the website.