Casual shirts are a popular type of clothing for everyday wear. They come in two main varieties: tees and polos. Tees, or t-shirts, are typically made of cotton and have short sleeves and a round neckline. Polos are usually made of a blend of cotton and polyester and feature a collar and two or three buttons at the neckline. Both tees and polos can be found in a variety of colors and styles, making them a versatile and comfortable choice for casual wear.