Quantum computers are computers that can compute almost instantly. Very few of these computers exist right now because they are extremely hard to make. In order to create this type of computer the microchips need to be cooled down to -460 degrees Fahrenheit. This temperature can only be reached by using liquefied helium. To this day, there are currently only 11 quantum computers in the world and only big companies such as Google and IBM have them.
Quantum computers are much better than a standard supercomputer because instead of encoding information in bits they encode information in qubits. Doing this, quantum computers can work on a million computations at once while even the most powerful supercomputers can only do one. The way this works is because when you store information in bits it limits you to only two states such as “up” and “down” but with a quantum computer you can be “up” and “down” or “on” and “off” at the same time, this is called superposition. Superposition is commonly known as a phenomena because it does not follow some of the common rules of natural physics.
Although these computers may seem cool (they are), they can also be very dangerous if they got into the wrong hands. With a computer that powerful, anyone could hack any online data almost instantly. It will also be the end of the Moore’s law because we will have the answers to anything almost instantly as well. Einstein even famously described this as “freaky”. Although in the future quantum computers may be available for general use, right now they are only to be used for research and experimentations only as people have not yet found out the solutions for the problems I have just described.