letter of confirmation(4uzhoj); certificate(a certificate is used to confirm that something has happened or does exist, rather than to confirm that something hasn't happened or doesn't exist.); verification letter(Yeldar Azanbayev); letter of verification(Letters of verification may be issued in lieu of certified copies (HRS §338-14.3). This document verifies the existence of a birth/death/civil union/marriage/divorce certificate on file with the Department of Health and any other information that the applicant provides to be verified relating to the vital event. ART Vancouver); letter(A letter confirms that something has not happened or does not exist, while a certificate confirms that something has happened or does exist • A letter confirming the non-registration for the birth, death, marriage or any other change of civil status.)
online help(The capability of many programs and operating systems to display advice or instructions for using their features when so requested by the user, as by a screen button or menu item or a function key)
to whom it may concern(в некоторых случаях эта фраза пишется вместо заголовка по центру страницы, и её вполне правомерно передать в переводе словом "справка". 4uzhoj)