1. Of course. A flashlight has a circuit
2. no. You have to be more specific before you get into details.
3. Well, at least back to the 1930's when the first digital computers were built. But you can probably go back earlier than that, for the first logic circuits.
But I can go back even earlier:
In a 1886 letter, Charles Sanders Peirce described how logical operations could be carried out by electrical switching circuits. Starting in 1898, Nikola Tesla filed for patents of devices containing electro-mechanical logic gate circuits. Eventually, vacuum tubes replaced relays for logic operations. Lee De Forest's modification, in 1907, of the Fleming valve can be used as AND logic gate. Ludwig Wittgenstein introduced a version of the 16-row truth table as proposition 5.101 of Tractatus Logico-Philosophicus (1921). Claude E. Shannon introduced the use of Boolean algebra in the analysis and design of switching circuits in 1937. Walther Bothe, inventor of the coincidence circuit, got part of the 1954 Nobel Prize in physics, for the first modern electronic AND gate in 1924. Active research is taking place in molecular logic gates.