A sun hat is a type of headwear that is designed to protect the wearer from the sun's rays. The term 'sun hat' can refer to a variety of different styles, including the TOPI, which is a four-letter word meaning a brimless cap made of cloth, usually with a visor. Another type of sun hat is the TERAI, a five-letter word referring to a wide-brimmed hat made of straw or felt, often with a chin strap. Finally, the TOPEE is a five-letter word for a lightweight, brimmed hat made of cloth, typically with a wide brim and a flat crown. All of these types of sun hats are designed to provide protection from the sun's rays.