The term "K-Class" typically refers to a classification of star systems in astronomy, particularly those that contain K-type stars. K-type stars are cooler and less luminous than the more common G-type stars, like our Sun. They have a surface temperature ranging from about 3,900 to 5,200 Kelvin and are known for their orange hue. These stars can have a long lifespan, making them interesting targets for the search for extraterrestrial life. In addition to astronomy, "K-Class" can also refer to a category of vehicles or equipment, such as the K-Class submarines used by the Royal Navy during World War I. These submarines were designed for coastal defense and had a unique shape, allowing them to operate effectively in shallow waters. The K-Class submarines are notable for their innovative design, although they faced challenges in terms of reliability and performance.