A more thorough explanation:

Definition: In the United States, esquire (often shortened to Esq.) is a title of courtesy given to a lawyer. It is commonly added to the lawyer's surname when addressing them in written form. For example, John Smith, Esq. or John Smith, Esquire. It is not appropriate to add Esq. or Esquire to one's own name.

In England, esquire is a mostly obsolete courtesy title that is added to a man's name when he has no other title. Historically, the title was used for a member of the English gentry whose rank was superior to that of a gentleman but inferior to that of a knight.

Example: When writing a letter to a lawyer, it is appropriate to address them as John Smith, Esq. This shows respect for their profession and acknowledges their legal expertise.

Example: In England, a man without a title may be addressed as John Smith, Esquire. This is a way of showing respect and acknowledging their social status.

These examples illustrate how the title of esquire is used as a form of courtesy and respect in different contexts. In the United States, it is used to acknowledge a lawyer's professional status, while in England it is used to acknowledge a man's social status.