A simple explanation of the xerographic process follows:

Xerography is an electrophotographic printing process that produces printed images with the use of charged powder (toner) that is fused to the substrate. Original artwork is placed face down on the flat glass plate of a xerographic device. A light source beneath the glass plate moves across the artwork. The light is reflected from the original document onto a mirror and the mirror reflects the light onto an electrostatically charged drum where an image is formed. The image on the drum, which is invisible, is known as an electrostatic latent image. After exposure to light, the photoconductors discharge from the non-image areas of the drum. The drum passes along a toner roller and liquid or dry toner particles are attracted to the charged image areas of the drum. The paper receives a charge from a corona transfer assembly and when the drum makes contact with the charged paper, the toner is deposited onto the paper. The toners are fixed to the substrate with heat and pressure rollers. The drum is then cleaned of any remaining toner particles and the latent image is removed from the drum with an erase corona. Xerography is commonly known as photocopying. The primary components of a xerographic device are shown in the illustration below.

A simple explanation of the electrophotographic laser process follows:

A Laser Electrophotographic printing device combines a scanner and imagesetter into one system. The original artwork is digitally scanned and the digital information is imaged onto an electrostatic drum with the use of a laser light or LED (Light Emitting Diode). A document or image already stored on a computer can also be retrieved for imaging on the laser printer. Toner is attracted to the laser imaged areas of the drum, which is then deposited onto the substrate.

The toners can be a dry mixture or liquid. Dry toner images are fixed onto the substrate with heat and liquid toner images dry shortly after the liquid toner makes contact with the substrate. A minimum of 1800 dots per inch is required for high-quality print applications when using laser systems. The main components of a laser printer are shown in the illustration below.