This is the use of letters to indicate proper nouns or it used at beginning a sentence?

Here's the breakdown:

* Capital Letters for Proper Nouns: Proper nouns are names of specific people, places, or things. These always start with a capital letter.

* Examples:

* Peter, France, The Eiffel Tower, Christmas, Monday

* Capital Letters at the Beginning of a Sentence: Every sentence begins with a capital letter.

* Examples:

* The cat sat on the mat.

* It was a beautiful day.

Let me know if you have any other questions about capitalization!