Group 3 refers to a category of elements in the periodic table, specifically the group that includes the chemical elements Scandium (Sc), Yttrium (Y), and the Lanthanides. These elements are known for their similar properties, such as having three electrons in their outermost shell, which influences their chemical behavior. The elements in Group 3 are often used in various applications, including electronics, lighting, and materials science. For example, Yttrium is commonly used in LED lights, while Scandium is utilized in aerospace components due to its lightweight and strong characteristics.