Answer 1

Greetings. This question is published frequently, so you will find an answer to it in subsequent threads. In the same way, please use the search bar before posting to avoid duplicate threads.
- https://www.sololearn.com/Discuss/1316935/?ref=app
- https://www.sololearn.com/Discuss/1302906/?ref=app

Answer 2

some combo of quantum physics and advanced computer science

Answer 3

A normal computer works in Binary(1's and 0's) while a quantum computer can be more than that(superposition or two dimensional). That's about all I know.
https://en.wikipedia.org/wiki/Qubit
I've never really bean able to understand it.
Hopefully some engineers will come along to explain.

Answer 4

Quantum Computers will be more powerful & faster than Super Computes. But they in developing process, no Quantum Computer is built yet.

Answer 5

Imagine having 8 bits. They can have 256 different states and have to switch between those for every calculation. 8 qubits on the other hand have 256 states at the same time. This means that, when using bits, for each bit you add, your time and space needed for the calculation will rise exponentially, whereas when using qubits, the time will stay almost constant, but actually the price will rise exponentially.
Quantum computers will be used to do calculations in minutes/hours that would otherwise take days/weeks/months. The problem is, due to the principle of quantum mechanics, once observed, the wave function of the qubits will collapse - in other words, once you get a result, you have to replace all the qubits. Therefore, you'll have weeks of planning, writing and revising code for a single calculation, because you don't want to waste millions of dollars on bugs. I suggest downloading the Android app "Quantum" by Štěpán Brychta, it explains quantum mechanics so simply that non-physicists can understand it.
Quantum computers are an expensive kind of fun and even in science they'll only be used for extremely complex calculations. It's an interesting topic, but in my opinion it's not worth getting into it if you're not a physicist or otherwise very specialised.