the operating system the man page or subject source is developed
or modified for,
and the man page title
-.Pq Em in upper case
+.Pq Em in uppercase
along with the section of the manual the page
belongs in.
These macros identify the page,
option is valid only for manual page sections 2 and 3.
.Ss Trade Names (or Acronyms and Type Names)
The trade name macro is generally a small caps macro for
-all upper case words longer than two characters.
+all uppercase words longer than two characters.
.Pp
.Dl Usage: .Tn symbol ... \*(Pu
.Bl -tag -width "\&.Tn ASCII" -compact -offset 14n
And adding to the muddle,
.Xr troff
has its own internal registers all of which are either
-two lower case characters or a dot plus a letter or metacharacter
+two lowercase characters or a dot plus a letter or metacharacter
character.
In one of the introduction examples, it was shown how to
prevent the interpretation of a macro name with the escape sequence