In English the Articles and nouns go hand in hand, so without understanding how nouns work you can't really get the hang of how the articles work.
Now it should be noted right off the bat that what I'm talking about here are common nouns, as opposed to proper nouns. Proper nouns are basically names, like the names of people or cities or countries etc. And common nouns, well in essence, they're names too but a common noun never refers to a truly unique object.
Now, when it comes to common nouns, I think everybody who's been studying English for any length of time probably knows that in English a noun can be countable or uncountable. It has to be noted here, that in actuality it's not really nouns that can be countable or uncountable but rather it's their meanings. And it's a very important point that it's really worth bearing in mind; when we're talking about countability or uncountability it's the countability or uncountability of the meaning not a word.
For example - when chicken means a bird it's countable and we say 'I saw a chicken the other day' but when it means meat then we say 'I had chicken for dinner last night' because now, even though, it's the same word, it's used in an uncountable meaning.
So, with the countability vs uncountability issue cleared up we can proceed to the articles themselves.
The first question I want to ask you is how many articles do you think there are in English? It's a rhetorical question, not a quiz. Well, me, the way I understand it there are just two articles; the definite article and the indefinite article. Their names are of little help, to tell you the truth, so when I think about them I prefer to call them the specifying article and the classifying article as one of them specifies which thing we're talking about and the other classifies or essentially names what we're talking about. Have you guessed which is which yet? Ok, the is the specifying article and a/an/- is the classifying article.
In case you haven't noticed, I wrote that the classifying article is a/an/-. Yes you got me right. The way I see it, in English every common noun is ALWAYS preceeded by an article, which can be either the specifying article 'the' or the classifying article which can take one of three forms - a, an or zero (that is when there is nothing in front of the noun).
This last point is very important, imho, so I'll repeat it; an English common noun always has an article in front of it, it's just that sometimes the article can be 'invisible'. Why I think looking at it this way makes more sense than saying that sometimes English common nouns can be used without an article - well, the article in front of a noun adds meaning to the noun by telling us whether the other person is talking about something specific we're both supposed to know about or whether they're introducing some new information, now the thing is that it's simply a quirk of the history of the English language that the classifying article in its 'visible' form a/an originated from the numeral one and thus people don't use it in front of plural and uncountable nouns.
The fact remains, though, that when there's no article or zero article in front of a noun, the noun is used in its general classifying sense.
So where does this leave us?
It gives us a very simple, straightforward and easy to remember rule for using articles with common nouns:
1. If it's something specific you're talking about you specify it with 'the' and it doesn't matter if the noun is countable or uncountable, singular or plural, a mass noun or an abstract idea it will always be 'the' thing.
2. If you're naming a thing, classifying it, introducing a new concept into the conversation (or should I perhaps say the discourse), then you use the classifying article in front of it and now it comes down to choosing the right form of the classifying article:
- if your noun is uncountable then the form is zero, i.e. no article;
- If your noun is countable but plural, then once again the form is zero - no article
- If your noun is countable and singular and starts with a consonant then use 'a'
- If it's countable, singular and starts with a vowel sound then use 'an'
Hope this helps y'all.