@@ -213,6 +213,25 @@ Try using the
 and
 .I pwd
 commands in different ways.
+.I cd .
+changes the current directory to the path to the current directory;
+this does nothing.
+.I cd ..
+changes the current directory to the parent directory of the current
+directory.
+For instance, if our current directory is
+.I /home/aeb
+and we change the current directory to
+.IR .. ,
+the current directory will now be
+.IR /home .
+.I cd /
+changes the current directory to the root of the hierarchy.
+.I cd \[ti]
+changes the current directory to the user's home; if I am logged in as
+.IR aeb ,
+this command will change my current directory to
+.IR /home/aeb .
 .SS Directories
 The command
 .I mkdir