The development history of pens can be divided into three periods: (1) At first, pens were born from branches, sticks and bones used to draw symbols on the ground. However, it is this simplest thing that draws the oldest human characters. Ancient Sumerians used this pen to draw world-famous simplified Chinese characters on clay tablets, and charcoal sticks could draw black marks. The ancient Egyptians used it to record hieroglyphics. Later, because Oracle Bone Inscriptions and the inscription appeared on the carrier of words, there was a knife and pencil. Knives and pencils are also rod-shaped and seem to be used to handle hard Oracle Bone Inscriptions and stones. Since the ancients found that carbon sticks can be used to write, they have been using this method. Graphite can also be used to write, but it is easy to get dirty with carbon sticks or graphite sticks. Smart people put a coat on charcoal sticks and graphite sticks, mostly cork. That is, the current pencil, its biggest feature is that the handwriting is easy to change. Once the eraser is wiped, the handwriting is completely gone. (2) With the development of writing carrier to cloth, silk and bamboo slips, the period of using sticks instead of pens gradually ended, and the second generation of dip pens began to appear. Among them, the brush is the best, with bamboo as the pole and animal hair as the nib. Animal hair has moderate hardness and strong water absorption, but because the brush is suitable for brushes, the pen speed is too high, so another form of dipping pen-feather pen appears. It is found that the long feathers at the tail of bird wings are hard and suitable to be held by hands, and the quill is hollow, so it is quite convenient to dip in ink, so the quill pen came into being, but it has many shortcomings, such as the water quantity of quill pen is not easy to control and the handwriting is thick and thin. I can't let ink drip on the paper. (3) The portable pen period was from 65438 to the mid-1980s. The pen was invented on the basis of the quill pen, which quickly replaced the traditional quill pen and became the main writing tool in the 20th century. Pen, also known as fountain pen, is a portable pen made according to the principle of air pressure. The pen container is a small empty cylinder, and the air is exhausted by squeezing. After release, the internal volume of the space increases and the pressure decreases. The greater pressure inside and outside makes the ink suck into the pen holder, and the pressed ink flows out with the pen tip under the action of gravity, so that writing does not need to be dipped in ink continuously, which greatly saves time and makes writing smooth and convenient. Later, a ballpoint pen was invented, which was more convenient for writing. Because it is an oily writing material, it avoids the trouble that the pen will leak ink, and the writing time is longer, lighter, more convenient and more economical, so it is deeply loved by modern people.