Josephine Cochrane was a wealthy woman and had engineering in her blood as her grandfather John Fitch was famous for inventing the steamboat. She also liked to entertain friends frequently and hold social events at her home resulting in a lot of dishes needing to be cleaned each time. The crockery she used for entertaining was expensive and was often getting broken by the servants while washing up. Getting fed up with this she decided to build a dishwasher that could wash dishes quickly without breaking them. She built a machine consisting of a wooden wheel lying flat in a copper boiler which could be turned either by hand or driven by a power source via a pulley. Wire framed compartments made to fit her dishes were attached to this wheel and the combination of it spinning and soapy hot water being showered on them by the boiler resulted in the first efficient dishwasher.
She took her dishwasher to the world fair in 1893 in Chicago where it won the highest award and people ranging from friends to hotel and restaurant owners were queuing up asking for a dishwasher machine of their own. Quickly she patented the invention and opened a production factory to build them and this company became the household appliance giant today known as KitchenAid. More companies also started making other versions some with conveyor belts and others with baskets spun by various methods both using a jet or spray of hot water poured from above to clean the dishes.
It wasn't till the 1920's that any significant advances were made to the design of these machines when permanent plumbing was introduced to hook them up to a constant water supply. Only restaurants, hotels and wealthy families had these appliances as they were large and expensive and it wasn't till 1937 that a dishwasher small enough for a home was built. It was built by William Howard Livens and looked more like the washers we have today with mesh baskets inside a metal container and a front opening door with a drying element introduced into its design in 1940. Gradually they became smaller, cheaper and more efficient and by the end of the 50s were getting more popular as a home kitchen appliance. Popularity continued to increase with most homes in the USA owning one by the end of the 70s. Today they are popular all through Europe and the Middle East where they took longer to catch on than in the USA.
A large range is available today with many big name manufacturers like Whirlpool, Bosch Maytag, GE and many other creating a very competitive market.