While in some languages, you can say "I buy book", in Dutch, you have to add an article: "I buy 'a' book". This is no novelty to English speakers. Not only do we have to add an article, we also have to choose between a definite (the book) and an indefinite article (a book).
The Dutch go one step further: If you decide that you buy the book (definite article), there are two definite articles to choose from: 'De' and 'het'. Which one you need to use, depends on the gender of the noun. I can already reveal that in Dutch, the book is neuter and therefore, 'het boek'. You will read more about articles on the next page.
The most important things you need to know about nouns is how to form plurals and diminutives (small nouns). We will also look at this typically Dutch phenomenon: The compound noun. But let us first have a look at the Dutch articles.