MTAB, or Mount Table, is like a special list that your computer keeps to remember all the different devices and things that it has connected to or "mounted" onto itself. These devices could be things like USB drives, external hard drives, or network drives.
So, let's say you plug in a USB drive to your computer. The computer needs to remember that it has done this, and that the USB drive is now available to use. MTAB is like a little notebook that your computer uses to write down this information, so it can look back at it later if it needs to.
MTAB lists all the devices and things that are "mounted" onto your computer, along with information about how they were mounted and where they are located. It's like a little reference book that your computer can use to find things quickly and easily.
MTAB can be really helpful because it makes it easy for you to find and access all the different devices and things that your computer has connected to. It's like having a map that shows you where everything is located.