Determiners
Articles: the
  vs. zero article
  -  The oranges are
    on the table. 
 The = article
  -  Oranges are grown in Spain.
 ___Oranges = zero
    article
The zero article is used with indefinite
  plurals and uncountable nouns. We use it when we are talking about these things
  in general.
  - Chocolate is made from cacao beans. 
 NOT: The chocolate is made from cacao beans.
- Oranges are grown in Spain.
 NOT:  The oranges are grown in Spain.
- I like dogs.
 NOT:  I like the dogs.
The article the
  (definite article) is used with specific
  plurals and uncountable nouns.
  -  The chocolate is expensive in this shop.
    (definite article: Which chocolate? The
    chocolate in this shop.)
-  The oranges on the table are for dessert.
    (definite article: Which oranges? The oranges
    on the table.)
Here are more examples to compare:
  -  I like music.
-  The music is very loud in this bar.
  - She's very interested in poetry.
-  The poetry in this magazine is excellent.
  - Books are expensive.
-  Put the books on the table.
 In scientific and technical language we can use the
  in generalizations with singular countable nouns,
  to talk about the whole class of things. For example:
  - The koala can climb trees.
- Koalas can climb trees.
 NOT:  The koalas can climb trees.