The comma, the full stop, but an asterisk, and an ellipsis?

For what reason Wikipedia lists comma as the comma, full stop as the full stop, ampersand as the ampersand, but asterisk as an asterisk, and ellipsis as an ellipsis?

For what reason Wikipedia use different articles for them? Does it mean that it is assumed that the last two are probably unknown to an average reader?

Solution 1:

There's probably no reason for it. It makes very little difference whether an article begins with "the comma" or "a comma"; they mean the same thing and there's not much reason to choose one over the other.

In particular, the use of "a" instead of "the" does not indicate that asterisks or ellipses are probably unknown to an average reader.

The only difference—and it's a very small difference—is that if the article starts with "the comma", it's talking about the type of punctuation mark which is called "comma", and if it starts with "a comma", it's talking about individual punctuation marks that are commas. But this makes no difference at all.

By the way, after this question was posted, the Stack Exchange user choster wrote in a comment:

Ellipsis only gained an article in February 2017, whereas asterisk has started as an asterisk since the creation. Tell you what, I'm going to make the question moot.

choster then edited the Wikipedia articles "asterisk" and "ellipses" so that now, all five articles start with "the".

Solution 2:

[...] Wikipedia lists comma as the comma, full stop as the full stop, ampersand as the ampersand, but asterisk as an asterisk, and ellipsis as an ellipsis?

Regardless of the properly edited or not properly edited text on Wikipedia, the point is the following:

Any noun discussed as a category in English can begin with the. It is used in formal sentences or explanations, usually in writing and not in speech.

• The horse is a noble animal.
• The apple is good for your health.

Used in this manner, the the refers to a type or category.

• Semantically, The horse is a noble animal. = Horses are noble animals.

So, "The comma" as used in Wikipedia is a formal way of saying: Commas etc.

In speech, we are apt to say: Commas are x and not The comma is x.

MIT instructions to students:

You can also use the definite article with a singular countable noun to refer to the entire class that the noun belongs to. This is often done with species of animals, inventions, or musical instruments:

The honey possum of Australia is the only mammal that lives exclusively on nectar.
--"Take It or Leave It," Valley Comic News

If making categorical formal statements, one can begin with the and move to a. OR one can begin with the plural noun.

• The comma is an interesting punctuation mark.
• Commas are interesting punctuation marks.

If you use a comma as the subject, you won't be making a generic statement about commas.

• A comma may or may not be used after certain phrases.

BUT NOT: A comma is an interesting punctuation mark.

MIT and use of the definite article the