The term "glass blowing" refers to a process whereby molten glass is molded into different shapes by means of a blowpipe, a hollow metal tube. A blowpipe is used to collect molten glass, which is subsequently shaped into a bubble or hollow by blowing air through the pipe. The shape can then be altered by the glassblower using a variety of tools and techniques to blow, shape, and cool the glass. Over the course of many centuries, the art and technique of glassblowing have developed. Sculptures, vases, ornaments, and decorative items made of intricately blown glass are the work of skilled artisans. Managing the glass's temperature and form is an art form that demands great precision and talent, but also offers great pleasure to those who master it. Many modern-day fields make use of glassblowing techniques, such as the arts, design, and manufacturing.