excel.exe is the main executable for Microsoft Excel.
Excel is a spreadsheet program included in Microsoft Office Suite. This process should not be removed with XL documents open.
Non-system processes like excel.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