Capitalize proper nouns (those naming specific persons, places, and things) and most adjectives formed from proper nouns. All other nouns are common nouns and are not capitalized unless they are used as part of a proper noun: a street, but Elm Street.

Capitalized nouns and adjectives include personal names; nations, nationalities, and languages; months, days of the week, and holidays (but not seasons of the year); geographical names; structures and monuments; ships, trains, aircraft, and spacecraft; organizations, businesses, and government institutions; academic institutions and courses; historical events and eras; and religions, their deities, followers, and sacred writings. For trade names, follow the capitalization you see in company advertising or on the product itself.