1.\" Copyright (c) 1989, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)caesar.6 8.2 (Berkeley) 11/16/93 7.\" 8.Dd 9.Dt CAESAR 6 10.Os 11.Sh NAME 12.Nm caesar 13.Nd decrypt caesar cyphers 14.Sh SYNOPSIS 15.Nm caesar 16.Op Ar rotation 17.Sh DESCRIPTION 18The 19.Nm caesar 20utility attempts to decrypt caesar cyphers using English letter frequency 21statistics. 22.Nm Caesar 23reads from the standard input and writes to the standard output. 24.Pp 25The optional numerical argument 26Ar rotation 27may be used to specify a specific rotation value. 28.Pp 29The frequency (from most common to least) of English letters is as follows: 30.Pp 31.Bd -filled -offset indent 32ETAONRISHDLFCMUGPYWBVKXJQZ 33.Ed 34.Pp 35Their frequencies as a percentage are as follows: 36.Pp 37.Bd -filled -offset indent 38E(13), T(10.5), A(8.1), O(7.9), N(7.1), R(6.8), I(6.3), S(6.1), H(5.2), 39D(3.8), L(3.4), F(2.9), C(2.7), M(2.5), U(2.4), G(2), 40P(1.9), Y(1.9), 41W(1.5), B(1.4), V(.9), K(.4), X(.15), J(.13), Q(.11), Z(.07). 42.Ed 43.Pp 44Rotated postings to 45.Tn USENET 46and some of the databases used by the 47.Xr fortune 6 48program are rotated by 13 characters. 49