Vasovagal Syncope. Vasovagal syncope is a common cause of fainting. The vagus nerve is overstimulated and causes the body's blood vessels to dilate and the heart to slow down. This anti-adrenaline effect decreases the ability of the heart to pump blood upward to the brain against gravity. Without blood flow, the brain turns off.
Enigma. The Enigma machine is a piece of spook hardware invented by a German and used by Britain's codebreakers as a way of deciphering German signals traffic during World War Two.hoto: A four-rotor German Enigma cipher machine made during WW2. This rare machine is thought to have been used in the post-war years for coding Swiss diplomatic traffic. (SSPL/Getty Images).
The input that is inscribed on the tape before the computation starts must consist of a finite number of symbols. However, the tape is of unbounded length--for Turing's aim was to show that there are tasks that these machines are unable to perform, even given unlimited working memory and unlimited time. Turing machine is an idealised computing device consisting of a read/write head (or 'scanner') with a paper tape passing through it. The tape is divided into squares, each square bearing a single symbol--'0' or '1', for example.