Paper recording charts and consumables consist of circular charts, strip charts, markers, fanfolds, sheets, pens, and pen arms used in chart and strip recording instruments. A chart recorder is an instrument used to record various process and electrical signals. The paper is passed under a pen and the pen is deflected in proportion to the signal. The result is a graph or chart of the data. There are many types of paper recording charts. Examples include circular charts and strip charts. Circular charts are used in circular chart recorders which record data in a circular format. The paper is spun beneath one or more pens. The pens are deflected in proportion to the varying signal resulting in a circular chart. Strip charts are used in strip chart recorders which consist of a roll or strip of paper that is passed linearly beneath one or more pens. As the signal changes the pens deflect, producing the resultant chart. Paper recording consumables refers to various other instruments and materials, such as sheets, paper, and pens, which are used in a chart recorder. Other paper recording charts and consumables are commonly available.