Language/Icelandic/Grammar/Definite-Article
You may not have learned this at school, but in English the word “the” is called a definite article. That is because the word “the” points to a very specific thing. For example, you may tell someone, “I want the book,” assuming that they will bring you the book you have in mind.
However, if you tell them, “I want a book,” you will get whatever book they choose to hand you! That is because the words “a” or “an” or “some” are indefinite articles and point to a general group of items, things, people or places.
Icelandic is unusual in that it does not have an indefinite article. It does have a definite article and unlike English, the definite article is not placed in front of the noun but is attached to its end like a suffix. You should first decline a noun and then add the article. The definite article varies per case, gender and number.