Official letters are formal communications used in professional or governmental contexts. They often follow a specific format and are used to convey important information, requests, or decisions. Common examples include letters from government agencies, businesses, or educational institutions. These letters typically include a clear subject line, a formal greeting, the main content, and a closing signature. They are important for maintaining professionalism and clarity in communication, ensuring that the message is understood and documented. Proper etiquette and structure are essential in crafting effective official letters.