1. A person who comments on blogs, newspaper articles, or something similar, but does not necessarily go as far as writing a full blog, or replying via "blogging" to respond. A comment can be as long or as short as you would like it or are limited to. Full sentences and paragraphs are ok, while versions of shorthand would also be ok in most scenarios.
2. A person who hits the "Comment" button associated with many social networking sites and actions reported to you by other users.
3. Do not get this confused with a troll. This person does not specifically have an agenda to drive the conversation or even one other user either way, but this person is also welcome to leave their opinion in one comment.
4. A comment can be of any size and us usually dictated by the parameters of the box one is given to write or mark comments in.
EXAMPLE OF COMMENTING ON SOMEONES STATUS ON A SOCIAL NETWORKING SITE
"Blue is a color" <Click to comment>
EXAMPLE OF A NEWSPAPER OR NEWS SITE:
"The Rain Fell Today in Chicago --
So much rain for the Windy City, this feels like a small hurricane -- Signed, local newswoman" <Click to leave comments>
<comment by commenter 1> "Dumb news story -CMNT"
EXAMPLE OF A SUGGESTION COMMENT BOX:
"Please place suggestions in the box."