For the purposes of understanding how articles are used, it is important to know that nouns can be either count (can be counted) or noncount (indefinite in quantity and cannot be counted). In addition, count nouns are either singular (one) or plural (more than one). Noncount nouns are always in singular form.
For example, if we are speaking of water that has been spilled on the table, there can be one drop (singular) or two or more drops (plural) of water on the table. The word drop in this example is a count noun because we can count the number of drops. Therefore, according to the rules applying to count nouns, the word drop would use the articles a or the.
However, if we are speaking of water in general spilled on the table, it would not be appropriate to count one water or two waters — there would simply be water on the table. Water is a noncount noun. Therefore, according to the rules applying to noncount nouns, the word water would use no article or the, but not a.
Following are the three specific rules which explain the use of definite and indefinite articles.
