The old days washboards and rivers are over. The first electric washing machines came about in the early 1900's. This revolutionized laundry cleaning and transformed a task that used to take hours of labor into a task that takes a little bit waiting and a few minutes of labor. Similar to the growth of the washing machine came the growth of the laundromat. Just like today people would go to the laundromat with a pocket full of change, load up their laundry, and kill time until they can take their clean clothes home.
Modern day machines are typically "front load" or "top load". Both machines churn clothes in mixture and detergent, followed by a rinse cycle and then a spin cycle to dry the clothes. Front loading washing machines have an advantage because they can be stacked and fitted into tight places. Front loading machines are also believed to clean clothes more thoroughly. Top loading washing machines have the advantage of price(at least in the US), they also usually finish cleaning faster and can be opening any time during the cycle.
Many machines today are much more efficient than the machines of previous years. Recently there has been an emphasis on producing machines that can clean clothes with less water and energy. Like many appliances, washing machines can have an Energy Star label, meaning they have met specific energy efficiency requirements. These machines are often effecient enough that the consumer's energy savings are more than the cost of the machine after just a few years of use.