The name of a particular person, place, or thing is called a proper noun. The first letter of such a word is capitalized.
Capitalize people’s names, names of political and geographical places, names of particular buildings or streets or events, languages, nationalities, or religions. The list of illustrations will help you to distinguish between the particular and the general:
a large continent
Hyde Park High School
in high school
a college graduate
St. Luke’s Hospital
in the hospital
the Middle West
the Far East
east of the river
The President addressed Congress
the president of my club
becoming a priest
Capitalize references to the Deity and the Bible: God, Old Testament; but the Greek gods, sacred books of the Hindus.
Capitalize names of planets or constellations, but not the sun, the moon, or the earth: Mars, Saturn, the Big Dipper, stars, planets.
Capitalize days of the week and names of months, but not names of seasons: Wednesday, December, summer, winter