Determiners are special adjectives that identify the noun being described or that specify the quantity of the noun. They include demonstrative adjectives, possessive adjectives, and quantifiers, as well as articles.
A noun phrase usually contains only one determiner, and that determiner precedes all other adjectives.
Alain J. Martin, a computer scientist at the California
Institute of Technology who built the first asynchronous
microprocessor in 1989, says his tools, which Caltech plans
to license, can mathematically prove that a design is correct
before it is built, avoiding embarrassments such as the
division bug in Intel's Pentium processor.
--W. Wayt, "Turning Back the Clock," Scientific American (modified)