Add a couple of examples.

Obtained from:	OpenBSD

usr.bin/head/head.1

@@ -28,7 +28,7 @@
 .\"	@(#)head.1	8.1 (Berkeley) 6/6/93
 .\" $FreeBSD$
 .\"
-.Dd June 6, 1993
+.Dd March 16, 2013 
 .Dt HEAD 1
 .Os
 .Sh NAME
@@ -57,6 +57,19 @@ where
 is the name of the file.
 .Sh EXIT STATUS
 .Ex -std
+.Sh EXAMPLES
+To display the first 500 lines of the file
+.Ar foo :
+.Pp
+.Dl $ head -n 500 foo
+.Pp
+.Nm
+can be used in conjunction with
+.Xr tail 1
+in the following way to, for example, display only line 500 from the file
+.Ar foo :
+.Pp
+.Dl $ head -n 500 foo | tail -n 1
 .Sh SEE ALSO
 .Xr tail 1
 .Sh HISTORY

usr.bin/tail/tail.1

@@ -31,7 +31,7 @@
 .\"	@(#)tail.1	8.1 (Berkeley) 6/6/93
 .\" $FreeBSD$
 .\"
-.Dd June 5, 2009
+.Dd March 16, 2013 
 .Dt TAIL 1
 .Os
 .Sh NAME
@@ -147,6 +147,17 @@ is the name of the file unless
 flag is specified.
 .Sh EXIT STATUS
 .Ex -std
+.Sh EXAMPLES
+To display the last 500 lines of the file
+.Ar foo :
+.Pp
+.Dl $ tail -n 500 foo
+.Pp
+Keep
+.Pa /var/log/messages
+open, displaying to the standard output anything appended to the file:
+.Pp
+.Dl $ tail -f /var/log/messages
 .Sh SEE ALSO
 .Xr cat 1 ,
 .Xr head 1 ,