A communication which can not be disclosed without the consent of the party making it, – such as those made by a client to his legal adviser, or by persons to their religious or medical advisers

A communication which does not expose the party making it to indictment for libel, – such as those made by persons communicating confidentially with a government, persons consulted confidentially as to the character of servants, etc.

those to which a preference in payment is given out of the estate of a deceased person, or out of the estate of an insolvent.

witnesses who are not obliged to testify as to certain things, as lawyers in relation to their dealings with their clients, and officers of state as to state secrets; also, by statute, clergymen and physicans are placed in the same category, so far as concerns information received by them professionally.