▫ -d file = True if the file exists and is a directory.

▫ -b file = True if the file exists and is block special file.

▫ -c file = True if the file exists and is character special file.

▫ -k file = True if the files' "sticky" bit is set.

▫ -f file = True if the file exists and is a regular file

▫ -e file = True if the file exists.

▫ -g file = True if the file exists and the set-group-id bit is set.

▫ -L file = True if the file exists and is a symbolic link.

▫ -p file = True if the file exists and is a named pipe.

▫ -r file = True if the file exists and is readable.

▫ -s file = True if the file exists and its size is greater than zero.

▫ -s file = True if the file exists and is a socket.

▫ -t fd = True if the file descriptor is opened on a terminal.

▫ -u file = True if the file exists and its set-user-id bit is set.

▫ -w file = True if the file exists and is writable.

▫ -x file = True if the file exists and is executable.

▫ -O file = True if the file exists and is owned by the effective user id.

▫ -G file = True if the file exists and is owned by the effective group id.

▫ file1 –nt file2 = True if file1 is newer, by modification date, than file2.

▫ file1 ot file2 = True if file1 is older than file2.

▫ file1 ef file2 = True if file1 and file2 have the same device and inode numbers.

▫ -z string = True if the length of the string is 0.

▫ -n string = True if the length of the string is non-zero.

▫ string1 = string2 = True if the strings are equal.

▫ string1 != string2 = True if the strings are not equal.

▫ !expr = True if the expr evaluates to false.

▫ expr1 –a expr2 = True if both expr1 and expr2 are true.

▫ expr1 –o expr2 = True is either expr1 or expr2 is true.