Ink is defined as a colored liquid used for writing and reading. Ink is the foundation for everyday functionality and communication. Ink constitutes homework, literature, business transactions. The problem, however, is that ink often goes unnoticed. People often don't realize that many things that are important to them are made up of ink. This is because the ink is not large and does not stand out, it just appears. Ink is simply something that is there and is expensive to replace. The history of ink goes back a long time, evolving over the centuries to become what it is today. Ink produced for writing originated in Egypt and China, originally dating back to around 2500 BC. This ink was made from soot bound together with gum. This paste was formed into sticks and dried before being mixed with water immediately before use. Ink from this period was only used for handwriting. Printing was later created by the Chinese in 3000 BC. The invention of the hair writing brush is attributed to the Chinese general Meng Tien. This allowed writing on silk rather than with bamboo pens on bamboo strips. Bamboo is heavy, bulky and uncomfortable, but for all its virtues, silk is expensive. They used a mixture of colored earth, soot and plant matter for pigments, mixed again with gums for a binder. Actual printing consisted of drawing ink onto movable plates outlined with letters and signs. Then in 1440, when Johannes Gutenberg invented the first movable type printing press, they began producing soot bound with linseed oil or varnish, materials extremely similar to those used today for ink. Later in 1772 colored ink was introduced, however drying agents for colored ink were only introduced in the 19th century.......half the paper......forms more quickly. Once the paint is created, dispersion of the pigment occurs. This happens when pigment particles clump together. These clumps need to be broken up and the pigment dispersed evenly through the resin. There are three main types of equipment used to do this. Shortly after dispersion, ink is created. The last step is the printing process. Printing is usually done using four different colors of ink: cyan, magenta, yellow, and black. These subtractive colors are chosen because by "overprinting" these inks all other colors imaginable can be formed. For example, red is produced by overprinting yellow and magenta, as yellow absorbs blue light and magenta absorbs green light, leaving pure red light behind. Black ink is used because although in theory cyan, magenta and yellow should add to give black, they actually produce brown.