realplay.exe is the main process belonging to Real Networks, Real Player which allows the playing of various video files such as MPEG and AVI. This process also installs a system tray icon onto your system tray bar. "This program is a non-essential system process, and is installed for ease of use. "
Non-system processes like realplay.exe originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that over time your registry suffers fragmentation and accumulates invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues