ELI5: What problems can quantum computers solve that regular computers can't?

Quantum computers can solve massive guessing games that involve testing billions of combinations all at once, helping us discover things like life-saving medicines and super-fast delivery routes that regular computers would take thousands of years to figure out.

Imagine you are trying to find your way out of a giant corn maze. A regular computer acts like a person walking down one path at a time. If it hits a dead end, it has to turn around, walk all the way back, and try the next path. It will find the exit eventually, but it takes a really long time. A quantum computer is like a bird that flies over the maze, or a magical mist that flows down every single path at the exact same moment to find the way out instantly.

Here is how that magical ability could change our everyday lives:

• Making better medicines: If a tiny bug makes people sick, scientists need to find a cure. A regular computer has to test how thousands of tiny puzzle pieces—called molecules—fit together one by one. A quantum computer can test all the puzzle pieces at the exact same time, helping scientists invent new, life-saving medicines in days instead of years.
• Fixing traffic jams: If thousands of cars and delivery trucks are on the road, a quantum computer can look at every street in a giant city at once. It can instantly tell every driver the best route so nobody gets stuck in traffic and packages arrive on time.
• Super batteries: It could help design new materials to create phone and car batteries that charge in just a few minutes and last for weeks.
• Accurate weather alerts: Predicting the weather involves tracking billions of air and water shifts. Quantum computers could predict severe storms and hurricanes much sooner, keeping families safe.