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In Mac OS System 7 and later, an alias is a small file that represents another object in a local, remote, or removable1 file system. It is similar to the Unix symbolic link, but with the added benefit of working even if the target file moves to another location on the same disk (in this case it acts like hard link, but the source and target of the link may be on different filesystems). As a descendant of BSD, Mac OS X supports Unix symbolic links as well.