Lasers play an important role in society today. They are used in a full range of applications, from medical procedures and surgery to entertainment and holography. Different lasers are used for various applications. Two of the most common lasers are argon and diode.Invented in 1964 by William Hughes, the argon laser is part of a family of ion lasers marked by their use of noble gas as an active medium. Argon lasers have many purposes, including, but not limited to, forensic medicine, general surgery, and ophthalmic surgery. These lasers are also used for entertainment and holographic purposes. In spite of the many helpful applications of argon lasers, it is important to note that viewing their emissions can be dangerous.A diode laser is a laser constructed of semi-conductor material. These lasers, often referred to as laser diodes, are powered through the application of electrical current. Diode lasers, typically small in size and weight, are used in numerous applications such as remote control devices, security systems, CD players, and laser printers. These lasers are also used in optical fiber systems, barcode readers, and laser printers. Diode lasers are even used in laser hair removal.Individuals can choose from a wide variety of devices containing these lasers. Products with argon or diode lasers are available both online and off. Some, such as the HeNe system, contain both.