Technology has become an important part of art. Many artists use computers to help them create pictures. Videos are used in modern sculptures installations. The materials used to create paintings or sculptures have developed over the years, from watercolour and oil paints to acrylics, and from stone and metals to plastics. Special machines are used to protect the artworks in art galleries, and also to restore old or damaged works. However, as sophisticated as technology has enabled the art world to be, art can still be created using recycled objects such as soup cans and plastic cups.