'article' is the name given to 'the' and 'a'.
'The' is definite article because we know the one or ones we are talking about.
'A' is called indefinite article because we are not referring to a definite thing or person.
In Spanish the word for 'a' changes according to whether the noun is masculine or feminine:
un hermano (a brother)
una madre (a mother)
the word for 'the' also changes to show singular or plural as well:
el hermano (the brother) los hermanos (the brothers)
la madre (the mother) las madres (the mothers)
funny fact: a+el= al (to the) and de+el= del (of the/from the) are the only two occasions when two words merge into one in Spanish.
