What type of nouns should be capitalized?

Capitalizing nouns is an important rule in English grammar, primarily applied to proper nouns. Proper nouns are specific names that refer to unique entities, such as places, people, organizations, or specific events. For instance, names like "New York," "Eiffel Tower," or "Dr. Smith" are capitalized because they denote a particular individual or unique location, distinguishing them from general categories.

In contrast, common nouns refer to general items or concepts (like “city” or “teacher”), and while they may appear in specific contexts, they do not require capitalization unless they begin a sentence or are part of a title. Abstract nouns signify ideas or concepts that cannot be touched or measured (like “happiness” or “freedom”), and they are also generally not capitalized unless they are part of a title or begin a sentence. Collective nouns refer to groups (like “team” or “flock”) and are treated similarly in terms of capitalization rules.

Thus, proper nouns are the only category among those listed that consistently need to be capitalized to indicate their specificity and uniqueness in the English language.