Chapter 2

1.  Which filesystem is used by modern operating systems?
   Modern operating systems use different filesystems: Windows and macOS use their respective proprietary formats, NTFS and APFS, while Linux systems mainly use EXT4.
2. What is an inode? What is inode 0 in Unix?
   An inode is a filesystem data structure representing a file. It stores information about a file, excluding the name and data.
   The inode 0 is reserved for the / folder.
3. What's the difference between PID and PPID?
   PID is the unique identifier for an existing process, while PPID is the identifier of the parent process. When an existing process creates another, the new process has a PPID equal to the existing process's PID.
4. How do you terminate a process running in the background?
   While a SIGINT signal can be sent to a foreground process by pressing Ctrl + C, for a background process...