(REPRESENTING versus APPLYING FILTERS)
Manner: another word for style
Mannerism: in painting this means making lines and shapes which are noticeable but do not represent anything.
Oddly, the term Mannerism is also used when referring to painters whose style was composed of elongated forms – exaggerating the distortions made by artists such as Michelangelo, particularly in the Last Judgement. In this sense, the term describes a style, not an affectation.
Consider drawing an egg. An artist may indicate the darkness on one side by using different techniques of shading scrubbing; hatching: cross-hatching; smudging; painting along the form or across the form. All mean the same thing: they all give the appearance of darkness.
However, if one of these procedures were carried out in such a way that it caused the viewer to notice the marks more than the darkness which they indicate, the manner of shading would have become a mannerism: an example of bad drawing.