`ln` - make links between files

ln [-s] [-f] target link_name

Options you will use

-s, --symbolic: Make a symbolic link instead of a hard link.
-f, --force: Remove an existing destination file.
-n, --no-dereference: If LINK_NAME is a symlink to a directory, replace the link instead of creating a link inside the directory.
-f, --force: Remove an existing destination first.

Gotchas

A hard link is another NAME for the same inode: the data lives until the last name is removed. A symlink is a small file holding a path - delete the target and it dangles. Hard links cannot cross filesystems or point at directories.

Taught in

4.13 Links and inodes

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