An embedded systems are systems designed to have minimal to no human interference. They can be defined as a combination of both hardware and software put together to achieve a specific task. Unlike a general purpose computer with engages in a wide range of functions, an embedded system only does what is required of it, and is "part of a whole", meaning they are usually part of larger system.
An embedded system used for the controlling of a washing machine, would most like have a means of taking input from the user and would display expected output(Action). This can be described as stimuli and response. Some of the components that may most likely be required in refrigerator could be a thermometer which maybe maybe used in temperature gauge.
Embedded systems for fridges and washing machine would fall into the category of Stand alone systems, with sensors or push button which take external stimuli and give output, buttons on a washing machine take input such as time, spin, and the likes and give response by reacting accordingly. There might also be certain washing machines which use microcontrollers, an LCD display and a speed monitor sensor all interfaced to a micro controller (components for receiving external stimuli). This would fall under Sophisticated Embedded system.