apache.exe is a web server application which is used to host Internet/Intranet web pages. This is a critical process where web hosting is concerned and should not be terminated without the web-administrators consent.
Non-system processes like apache.exe originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that your registry has suffered fragmentation and accumulated invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues