Scientific Letter is an original mail program that allows you to create messages including complex equations.

The equation editor used in the mailer allows you to create complex letters including equations at almost the same speed as typing standard text. Recipients of letters from Scientific Letter using other post programs will see the message text with equations included in it as a LaTeX notation.

In typical mail products, only TeX/LaTeX notation can be used to insert equations into a message. A document from any LaTeX equation editor can be attached to a message in complicated cases. This creates difficulties in typing, checking the correctness of the entered equations and reading such messages. Users of Scientific Letter do not have these problems.