What type of noun is always capitalized?

Common nouns are never capitalized. They always start with a lower-case letter. Proper nouns are always capitalized. They always start with an upper-case letter. Proper nouns are the nouns that are a specific person, place or thing. For example, a proper noun would be Tina.

Tina is the name of a certain girl which is why it would be capitalized and is a proper noun. Another proper noun would be Chicago. Chicago is the name of a specific city. Since it is a specific place, it should be capitalized.

Finally, the third type of noun is a thing and an example of a proper thing would be the Atlantic Ocean. An ocean is a thing and the specific ocean is Atlantic.