Didymo is a member of the group of single-celled aquatic plants (freshwater algae) known as diatoms. Although it is microscopic, didymo can form dense colonies called algal blooms which can be seen with the naked eye.
From a marketing perspective, publicity is one component of promotion which is one component of marketing. The other elements of the promotional mix are advertising, sales promotion, direct marketing and personal selling. Examples of promotional tactics include: 1  Announce an appointment.
Very simply, defamation is to spread bad reports about someone which could do them harm. Of course, the laws of defamation say more than that, but it is a good place to start. The verb is to defame and the words used are said to be defamatory.