|v. i.||1.||To make remarks, observations, or criticism; especially, to write notes on the works of an author, with a view to illustrate his meaning, or to explain particular passages; to write annotations; - often followed by on or upon.|
|v. t.||1.||To comment on.|
|n.||1.||A remark, observation, or criticism; gossip; discourse; talk.|
|2.||A note or observation intended to explain, illustrate, or criticise the meaning of a writing, book, etc.; explanation; annotation; exposition.|
|Noun||1.||comment - a statement that expresses a personal opinion or belief; "from time to time she contributed a personal comment on his account"|
|2.||comment - a written explanation or criticism or illustration that is added to a book or other textual material; "he wrote an extended comment on the proposal"|
|3.||comment - a report (often malicious) about the behavior of other people; "the divorce caused much gossip"|
|Verb||1.||comment - make or write a comment on; "he commented the paper of his colleague"|
|2.||comment - explain or interpret something|
|3.||comment - provide interlinear explanations for words or phrases; "He annotated on what his teacher had written"|
|(programming)||comment - (Or "remark") Explanatory text embedded in
program source (or less often data) intended to help human
readers understand it.|
Code completely without comments is often hard to read, but too heavily commented code isn't much better, especially if the comments are not kept up-to-date with changes to the code. Too much commenting may mean that the code is over-complicated. A good rule is to comment everything that needs it but write code that doesn't need much of it.
A particularly irksome form of over-commenting explains exactly what each statement does, even when it is obvious to any reasonably competant programmer, e.g.
/* Open the input file */ infd = open(input_file, O_RDONLY);