Final answer:
Mounting of a file system is the process of attaching a portion of the file system into the directory structure, enabling access to its files within the operating system's directory tree.
Step-by-step explanation:
Mounting of a file system refers to the process of attaching a portion of the file system into a directory structure of the operating system. When a file system is mounted, it becomes accessible to the user and the system's applications as if it were a part of the directory tree. This applies to various storage devices such as hard drives, CD-ROMs, USB drives, and network file systems. Mounting enables the operating system to read and write files to the device. For example, in Linux, when you insert a USB drive and mount it, you might mount it to a directory like '/mnt/usbdrive', and the files on the USB will appear under this directory path..