The evolution of the windows cleaning process has taken place over decades. The process has evolved from the manual process by humans, to the manual process with use of machines, to the sole use of machines to perform the cleaning (Albagul et al., 208). The manual process by humans was difficult and the humans could only do as much as they could reach, thereby leaving some places unattended. The manual process with the use of forklifts allowed the cleaners to clean windows in higher levels of the building, a task they could not perform without the help of machines.The breakthrough in the windows cleaning process came with the invention of the robots. The robots are self – operated thus reducing the risk of death and disabilities or injuries caused by falling off. The robots come with their hardware and software to ensure precision, speed and repetition for efficiency in cleaning windows. The hardware entails the construction, mechanical, electronic circuitry as well as the electrical element while the software entails the programming bit (Albagul et al., 209) to ensure the robot receives and executes orders as per its design and functionality.According to Albagul et al., (210) three motors allow the robot to clean in upward and downward motion as well as from right to left. It has two tanks; with one for the cleaning detergent and the other for water. The four limit switches allow the whipping bars to stay within limit thus keeping the wipers within the window dimensions. The DC motor is made from a permanent motor to regulate the speed of the robot while the limit switched serve to energize or de – energize the circuit accordingly. The rack and pinion ensure precision during the rotation of the steering wheel. The logic controllers are micro – programmable from the S7 – 200 series to enhance accuracy as well as effective communication with other intelligent devices. These features allow the robot to clean windows in high places to precision in an effective and efficient manner, reducing the risks that come with the tasks being performed by humans.Work CitedAlbagul, A. et al. “Design and Fabrication of an Automatic Window Cleaning Robot.” World Scientific and Engineering Academy and Society (WSEAS) (2010): 208-212. Print.