German articles would really be best modeled in a table of four dimensions, with axes for gender, number, case, and type of article. Alas, this is not possible in standard 2-D text form; thus I will follow convention and draw four tables for different article types, and place the plural in the gender row, as all plural articles are the same regardless of gender.
The use of articles in German generally parallels that of English, with one prominent exception: articles can precede the name of a person to add emphasis.
The tables below are sorted vertically by the four cases of German (nominative, accusative, dative, genitive), and horizontally by the three genders (masculine, feminine, and neuter) and plural.
German article tables
definite articles
| Masc Fem Neut | Pl.
Nom| der die das | die
Acc| den die das | die
Dat| dem der dem | den
Gen| des der des | der
Definite articles are generally equivalent to the English "the", and are used to refer to objects either previously identified in the conversation, or assumed already known to both speaker and listener (such as "the moon" or "the courthouse"). A definite noun denotes a particular person or thing.1
indefinite articles
| Masc Fem Neut
Nom| ein eine ein
Acc| einen eine ein
Dat| einem einer einem
Gen| eines einer eines
Indefinite articles are generally equivalent to the English "a" or "an", and are used to refer to objects not previously identified or assumed. An indefinite noun denotes membership in a class, but not a particular one member.2 Indefinite nouns are often used to introduce a thing into discourse, and later references to the thing introduced: "A cat fell from a tree. The cat landed on the tree's roots."
der-words and ein-words
So-called "der-words" and "ein-words" are essentially semantically enriched articles. Der-words decline similarly to the definite article, and ein-words exactly as the indefinite article. Also, German adjectives decline differently depending on whether they are preceeded by a der-word, an ein-word, or no article or article-like word.
der-words
| Masc Fem Neut | Pl.
Nom| -er -e -es | -e
Acc| -en -e -es | -e
Dat| -em -er -em | -en
Gen| -es -er -es | -er
Der-words are declined by removing the -er ending and adding the proper ending as shown in the table. Der-words include dieser (this), jeder (every), jener (that), mancher (some), solcher (such), and welcher (which).
ein-words
| Masc Fem Neut | Pl.
Nom| - -e - | -e
Acc| -en -e - | -e
Dat| -em -er -em | -en
Gen| -es -er -es | -er
Ein-words are declined by adding the proper ending as shown in the table. Ein-words include kein (no, not any) and the posessive adjectives: mein (my), dein (your), sein (his), ihr (her), unser (our), euer (y'all's), ihr (their), and Ihr (formal your).
(1) Webby: definite
(2) indefinite
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