What is inode?

When a file system is created, data structures that contain information about files are created. Each file has an inode and is identified by an inode number (often "i-number" or even shorter, "ino") in the file system where it resides. Inodes store information on files such as user and group ownership, access mode (read, write, execute permissions)and type of file. There is a fixed number of inodes, which indicates the maximum number of files each filesystem can hold.

A file's inode number can be found using the ls -i command,while the ls -l command will retrieve inode information.This is description of inode information  which it contain:     * The length of the file in bytes.
    * Device ID (this identifies the device containing the file).
    * The User ID of the file's owner.
    * The Group ID of the file.
    * The file mode, which determines what users can read,write and execute the file.
    * Timestamps telling when the inode itself was last modified (ctime, change time), the file content last modified (mtime, modification time), and last accessed (atime, access time).
    * A reference count telling how many hard links point to the inode.
    * Pointers to the disk blocks that store the file's content