Qiskit Terra

Qiskit is an open-source SDK for working with quantum computers at the level of circuits, transpilation, and pulse control. The qiskit-terra package is the foundational component, providing circuit construction, transpilation, simulation, and IBM Quantum backend access. As of version 2.x, the package is simply called 'qiskit' on PyPI (qiskit-terra is a legacy distribution). Current version: 2.4.1, with quarterly releases.