A T-shirt is a casual shirt with short sleeves and a round neckline, shaped like the letter T when you lay it flat. The name comes from this T-shape: the body of the shirt forms the vertical line, and the sleeves stretch out to form the horizontal line across the top.

T-shirts started as undergarments for soldiers and workers in the early 1900s, but by the 1950s, people began wearing them on their own as everyday clothing. Today, they're one of the most common pieces of clothing in the world. You can find plain T-shirts in every color, or T-shirts printed with logos, band names, funny sayings, sports teams, or artwork.

The simplicity of the T-shirt makes it incredibly versatile. You might wear a plain white T-shirt under a button-up shirt, a graphic T-shirt with your favorite superhero on it, or a sports T-shirt for your soccer team. Some people collect T-shirts from concerts, vacations, or special events as comfortable souvenirs. Organizations often print custom T-shirts to build team spirit or promote causes they care about.

The T-shirt's comfort and ease make it a wardrobe staple: you pull it on, and you're ready to go.