What was this chip called?

Majorana 1 is the chip Microsoft announced, built around an attempt to create topological qubits using an exotic state of matter associated with theorized particles called Majorana particles. The appeal is that topological qubits are designed to store information in a way inherently protected from small local disturbances, since the information depends on the overall shape of the quantum state rather than a single fragile detail, which in principle should make them more resistant to errors.

Willow and Eagle are chip names associated with other companies' superconducting-qubit programs rather than Microsoft's topological approach, so they do not represent the same physics or announcement.

The scientific community has been notably cautious about topological qubits, since claims of detecting the underlying Majorana-based states have previously been walked back after further scrutiny, making this one of the more closely watched and debated corners of quantum computing research.