Defamation is the publication of a statement which refers on a person’s reputation and tends to lower him in the estimation of right-thinking members of society generally or tends to make then shun or avoid him. 
The tort of defamation protects a person’s interest in his reputation. If the defendant had made an untrue statement, or what amounts to a statement, which is defamatory of the plaintiff, the plaintiff has a right of action against him unless the defendant can establish one of the special defenses available to an action for defamation. Since the tort of defamation protects the plaintiff’s reputation, and since reputation depends on what other people think of the plaintiff, the publication of the statement by the defendant to persons other than the plaintiff himself is an essential part of the tort –the purpose of the tort is not to protect the injured the feelings of the plaintiff. The tort goes beyond protecting their mere personal reputation of the plaintiff and extends to the protection of the reputation of his commercial and business undertakings.
The rules of the tort represent an attempt to strike a balance between two important and often competing interests, the public interest in freedom of speech and the private interest in marinating one’s reputation. The difficulty of achieving this balance is perhaps indicated by the fact that, though liability for a defamatory statement is strict and substantial damages might be recovered from the one making the defamatory statement, a large variety of defenses exist for the one who makes such a statement.
Regardless of whether a defamation action is framed in libel or slander, the claimant must always prove that the words, pictures, gestures, etc are defamatory. Secondly, the claimant must show that they refer to him and finally, that they were maliciously published. These are the three essentials elements in a defamation action.
There are 2 types of defamation: libel which is generally in a written format and Slander which is in an Oral format. Different rules are applicable to each. There is no tort unless there has been a communication of the defamatory matter to a third party
"... slander ... may be divided into five classes, as follows:
(1.) Words falsely spoken of a person which impute to the party the commission of some criminal offence involving moral turpitude, for which the party, if the charge is true, may be indicted and punished.
(2.) Words falsely spoken of a person which impute that the party is infected with some contagious disease, where, if the charge is true, it would exclude the party from society;
(3.) Defamatory words falsely spoken of a person, which impute to the party unfitness to perform the duties of an office or employment of profit, or the want of integrity in the discharge of the duties of such an office or employment.
(4.) Defamatory words falsely spoken of a party which prejudice such party in his or her profession or trade.
(5.) Defamatory words falsely spoken of a person, which, though not in themselves actionable, occasion the party special damage.
"Certain words, all admit, are in themselves actionable, because the natural consequence of what they impute to the party is damage, as if they import a charge that the party has been guilty of a criminal offence involving moral turpitude, or that the party is infected with a contagious distemper, or if they are prejudicial in a pecuniary sense to a person in office or to a person engaged as a livelihood in a profession or trade; but in all other cases the party who brings an action for words must show the damage he or she has suffered by the false speaking of the other party." ...