A CD writer is a device that allows users to create and record data onto compact discs, commonly known as CDs. It can write various types of data, including music, videos, and documents, making it a versatile tool for data storage and sharing. CD writers can be found in computers or as standalone devices. To use a CD writer, a blank CD is inserted, and the desired files are selected for burning. The process of writing data onto the CD is called "burning," and once completed, the CD can be used in any compatible player or device.