The cotton gin,  invented in 1793 by Eli Whitney, was designed to separate raw cotton fibers from  seeds and other foreign materials prior to baling and marketing. The design was  so efficient that it remains virtually unchanged to the present day.

American Eli Whitney  invents the cotton gin, a device that rapidly and effectively removes seeds from  cotton fiber. This task had previously been done by hand, making fiber  processing slow and expensive. The invention will help spur expansion of the  cotton industry in the southern United States. The South’s booming cotton  economy in turn will increase the reliance on slaves, owing to the  labor-intensive character of cotton harvesting.

Although the invention  of the cotton gin changed history, its inventor, Eli Whitney, did not reap much  of a profit. The gin made cotton cleaning so efficient that the crop became a  primary enterprise for the South. However, patent disputes and supply problems  kept Whitney from successfully producing the cotton gin. His later venture into  arms manufacturing was more fruitful, and Whitney became a strong promoter of  mass production and interchangeable parts.

The role of the cotton gin has changed dramatically  in the last 50 years to keep up with technological and production changes in the  cotton industry. At one time, the gin's only function was to remove cottonseed  from the fiber. Today, gins must not only separate the seed from the fiber, they  must also dry and clean the fiber and package it into bales before it reaches  the textile mill.

All gins differ in some aspects of the ginning  process. In the Southwest, for instance, gins are equipped with both saw and  roller gins: saw gins for ginning Upland cottons, and roller gins for ginning  Pima cotton, a cotton grown almost exclusively in this region of the Cotton  Belt. Elsewhere in the Cotton Belt, gins use only saw gins in their operation.