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In this video I would like to
tell you about hard and symbolic links.

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It's all about file names
and making them more accessible.

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File names are stored in an internal
structure that is known as the directory table.

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And a link is a pointer in the
directory that refers to another file or directory.

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And there's two
types of them.

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Hard links are pointing to the
same inode on the same file system.

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Now what is an inode? The
inode is the unique administration that exists

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for all files and in which
the properties of your files are stored.

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Symbolic links are shortcuts
and they add additional flexibility.

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Now symbolic links can exist on a directory,
which is not the case for hard links.

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You can also create cross device symbolic links
to point to files that exist on another device.

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In general, links can be useful to ensure
that specific information is available at different locations.

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Before I show you how to work with them, let me make
a drawing that is making it clear how exactly these links are organized.

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Let me explain hard links and symbolic links. In order
to understand we need to know a little bit more about

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the file Files is in the end all about blocks,
blocks of data that is stored to your hard disk.

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These blocks need to be made
accessible and they need to be managed.

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And in order to do so,
the Linux file system provides the inode.

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The inode is a complete administration
of a file. Every file, no matter

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which file system it is, has
an inode and one inode only.

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Now the funny thing about inodes is that
in the inode you don't have the name of

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the file. And for that reason you can
have multiple names like name one and name two.

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And these names are independent of one another. So it
doesn't matter which one you make first, doesn't matter which

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one you remove first. There is no dependency between
these names. They are just a pointer to the inode.

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Now these names is
what we call hard links.

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There's also
a symbolic link.

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And the difference is that the symbolic link
is a name that is pointing to a.

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So we have symbolic link one and we have symbolic link two. They
offer a little bit more flexibility as I will explain in a bit.

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But there's also one problem. If something happens to
name one, then your symbolic links become invalid. So

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there's a dependency relation there. Symbolic links go to
a name and they don't go to an inode.