inode

• Data structure that describes a file-system object (file, directory, etc.)
• includes metadata
• directory is a list of inodes, including an entry for itself, its parent and all of its children
• data may be called stat data (reference to stat syscall that provides the data to programs)
• ls -i prints the inode number in the first column

POSIX:

• device ID
• file serial numbers
• file mode
• link count (how many hard links point to the inode)
• user id
• group id
• device id if it is a device file
• size of file
• timestamps
• preferred I/O block size
• number of blocks allocated to this file