Key Difference: A pronoun is a word that is used to substitute a noun in a sentence. Proper nouns are the names of specific entities such as the names of people, places, etc.

Pronouns are a very resourceful tool to construct sentences in the English language easily. Pronouns basically are the words which are used to denote a noun already mentioned in the text. Multiple use of the names of persons, places, etc. in a piece of text can make it cumbersome. Pronouns provide a sensible option to eliminate such discomfort by making the text crisp and free-flowing.

For example:

Anna was late, so she hurried to school.

In the sentence above, the word ‘Anna’ is the noun, which is mentioned in the first part of the sentence. Mentioning this word again in the second part of the sentence would have made it look awkward and perhaps, required the sentence to be divided into two separate sentences. Hence, to avoid such a crisis, the pronoun ‘she’ is used to make the sentence free-flowing and unobstructed.

Proper nouns are a sub-category of nouns. Proper nouns stand for the names of specific entities. They are unique to the thing. The names of people, places, cities, historic sites, monuments, etc. fall under this category of nouns. They are often used to indicate possession as well. These nouns carry a very important syntax rule with them. The rule states that the first alphabets of these nouns should always be capitalized, irrespective of wherever these words feature in a sentence.

For example:

Bob, Marley and Tina are best friends.

In the sentence above, the words ‘Bob’, ‘Marley’ and ‘Tina’ are proper nouns. The reason for this is that these names belong to separate individuals. They cannot stand for all the other people in the world. They are the property of these three persons. Hence, these three names have their first alphabets in capital, and are classified as proper nouns.

Comparison between Pronoun and Proper Noun:

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