In the 1890s, electric bicycles were documented within various U.S. patents. For example, on 31 December 1895, Ogden Bolton Jr. was granted U.S. Patent 552,271 for a battery-powered bicycle with "6-pole brush-and-commutator direct current (DC) hub motor mounted in the rear wheel". There were no gears and the motor could draw up to 100 amperes (A) from a 10-volt battery.
Assembly was pretty simple and straightforward, there are some videos online explaining it. Definitely important to know how to switch it on, though -- pressing the "M" button for two seconds with the key in the "on" position. Despite being a heavy bike, it's very quick and nimble. I ride about 15 miles per day and was able to get two trips out of it before charging, riding fast. My only complaints are the squeaky brakes, and the front fender. Said fender is a bit too close to the tire on the front wheel and doesn't mount very securely, so it kept making very loud noises as it would catch the tire whenever I went over a bump or had to brake hard. I just took it off for the time being.
E-bikes use rechargeable batteries and the lighter ones can travel up to 25 to 32 km/h (16 to 20 mph), depending on local laws, while the more high-powered varieties can often do in excess of 45 km/h (28 mph). In some markets, such as Germany as of 2013, they are gaining in popularity and taking some market share away from conventional bicycles, while in others, such as China as of 2010, they are replacing fossil fuel-powered mopeds and small motorcycles.