Why it is called special of a business letter?

The term "special" in the context of a business letter often refers to its purpose or format that distinguishes it from regular correspondence. A special business letter typically addresses unique situations, such as proposals, formal invitations, or urgent communications, requiring a more structured and professional approach. Additionally, it may incorporate specific elements like a particular tone, layout, or additional documentation, making it stand out and ensuring it captures the recipient's attention effectively.