OTHER is an ADJECTIVE which refers to a person or thing that is different or distinct from one already mentioned or known about. OTHER es un adjetivo que refiere a una persona o cosa que es diferente o distinto de algo ya mencionado o conocido. EJ: Tell me about the other students in your class. ANOTHER is an ARTICLE which refers to an additional person or thing of the same type as one already mentioned or known about; one more; a further. ANOTHER es un artículo que hace referencia a una persona adicional o algo del mismo tipo ya mencionado o conocido; uno más; una más. EJ: I am hungry. Please give me another slice of pizza.

Sigh! "Another" is not an article. It is a deterniner or a pronoun. The Oxford Dictionary comes to the rescue again. http://www.oxforddictionaries.com/definition/english/another?q=another DETERMINER & PRONOUN 1Used to refer to an additional person or thing of the same type as one already mentioned or known about; one more; a further: [AS DETERMINER]: have another drink I didn’t say another word [AS PRONOUN]: she was to become another of his stars MORE EXAMPLE SENTENCES SYNONYMS 1.1 [AS DETERMINER] Used with a proper name to indicate someone or something’s similarity to the person or event specified: this will not be another Vietnam MORE EXAMPLE SENTENCES 2Used to refer to a different person or thing from one already mentioned or known about: [AS DETERMINER]: come back another day his wife left him for another man [AS PRONOUN]: moving from one place to another MORE EXAMPLE SENTENCES 2.1 [AS DETERMINER] Used to refer to someone sharing an attribute in common with the person already mentioned: his kiss with another man caused a tabloid rumpus MORE EXAMPLE SENTENCES Origin

See if this example can illustrate the difference from you: My wife likes sleeping with other men. So I am going to leave her for another woman.

OK. Let's get really serious. "Other" has a number of meanings. The most often used meaning is "different or distinct from the one or ones already mentioned or implied" - such as "other women", "other people". For the complete definitions, the good old Oxford Dictionary comes to the rescue again: http://www.oxforddictionaries.com/definition/english/other?q=other

Other = when you refer to a selection of items/things The other day I went to the movies Another = when you refer to an additional item/thing I would like another cup of coffee.