Answer Description

Explorer (located in C:\Windows\Explorer.exe by default) is the Windows System program used to view files and folders. Internet Explorer (IE) is used to view website, it is possible to use IE to view folders but this is not common and must be manually implemented.

Wikipedia

File Explorer, previously known as Windows Explorer, is a file manager application that is included with releases of the Microsoft Windows operating system from Windows 95 onwards. It provides a graphical user interface for accessing the file systems. It is also the component of the operating system that presents many user interface items on the screen such as the taskbar and desktop. Controlling the computer is possible without Windows Explorer running (for example, the File ▸ Run command in Task Manager on NT-derived versions of Windows will function without it, as will commands typed in a command prompt window).