T-shirts are a ubiquitous garment, known for their comfort and versatility, but their origins are less commonly understood. The term 'T-shirt' is derived from the garment's shape, which resembles the letter 'T' when laid flat. This design was first popularized in the late 19th and early 20th centuries, particularly among US military personnel who wore lightweight cotton shirts as undergarments. Initially referred to as 'training shirts', the garment gained traction among factory workers and laborers due to its practicality and comfort in hot conditions. As T-shirts transitioned from undergarments to outerwear, they became widely recognized in the early 20th century, with literary references contributing to their popularity. The 1950s marked a significant turning point, as Hollywood stars donned T-shirts on screen, elevating them to a global fashion statement. Today, T-shirts are not only a wardrobe essential but also carry a rich history that reflects their evolution from simple workwear to a symbol of style and comfort.