A company may have its own letter class, for setting letters in the company style. This section shows a simple implementation of such a class, although a real class would need more structure.
The class begins by announcing itself as |neplet.cls|.
\NeedsTeXFormat{LaTeX2e}
\ProvidesClass{neplet}[1995/04/01 NonExistent Press letter class]
Then this next bit passes any options on to the |letter| class, which
is loaded with the |a4paper| option.
\DeclareOption*{\PassOptionsToClass{\CurrentOption}{letter}}
\ProcessOptions
\LoadClass[a4paper]{letter}
In order to use the company letter head, it redefines the
|firstpage| page style: this is the page style that is used on
the first page of letters.
\renewcommand{\ps@firstpage}{%
\renewcommand{\@oddhead}{<letterhead goes here>}%
\renewcommand{\@oddfoot}{<letterfoot goes here>}%
}
And that's it!