A business letter is a formal written communication used in professional settings. It typically follows a specific format and is used for various purposes, such as making inquiries, providing information, or addressing issues. Common elements include the sender's address, date, recipient's address, greeting, body, closing, and signature. These letters can be sent via traditional mail or email and are often used by individuals, companies, and organizations to convey important messages. Proper etiquette and clarity are essential in a business letter to ensure the message is understood and taken seriously.