These options test other file characteristics.
True if file exists.
True if file exists and has a size greater than zero.
True if file1 is newer (according to modification date) than file2, or if file1 exists and file2 does not.
True if file1 is older (according to modification date) than file2, or if file2 exists and file1 does not.
True if file1 and file2 have the same device and inode numbers, i.e., if they are hard links to each other.
True if file exists and has been modified (mtime) since it was last read (atime).