# Quantum computing steps forward with 50-qubit prototype

Bit by qubit, scientists are edging closer to the realm where quantum computers will reign supreme.

IBM is testing a prototype quantum processor with 50 quantum bits, or qubits, the company announced November 10. That’s about the number needed to meet a sought-after milestone: demonstrating that quantum computers can perform specific tasks that are beyond the reach of traditional computers (*SN: 7/8/17, p. 28*).

Unlike standard bits, which represent either 0 or 1, qubits can indicate a combination of the two, using what’s called quantum superposition. This property allows quantum computers to perform certain kinds of calculations more quickly. But because qubits are finicky, scaling up is no easy task. Previously, IBM’s largest quantum processor boasted 17 qubits.

IBM also announced a 20-qubit processor that the company plans to make commercially available by the end of the year.