Qiskit is a software development kit for quantum information science, designed to facilitate research, education, and the execution of complex problems on quantum computers. Developed by IBM, Qiskit has grown into a thriving ecosystem with over 6 million installations and a wide range of tools and plugins. It supports a flexible circuit model and a retargetable transpiler, enabling the representation and optimization of circuits at various abstraction levels. Qiskit's architecture includes circuits, pass managers, and primitives, which form the core components of the software. It allows for end-to-end workflows, such as solving problems in condensed matter physics on quantum computers, demonstrating capabilities like circuit synthesis, optimization, and quantum-classical integration. Qiskit's design philosophy emphasizes modularity, performance, portability, and interoperability across abstraction levels. It supports dynamic circuits, which enable real-time classical computation and error mitigation. The software also includes integrated visualizations, a tensor ordering convention, and a range of computational primitives for sampling and estimating observable expectation values. Qiskit's ecosystem includes a variety of tools and plugins that extend its functionality for different tasks. The software is designed to be scalable and efficient, with a focus on performance and ease of use. The release of Qiskit 1.0 marks a significant milestone, indicating its maturity and stability. Qiskit's architecture and capabilities make it a powerful tool for quantum computing research and development.Qiskit is a software development kit for quantum information science, designed to facilitate research, education, and the execution of complex problems on quantum computers. Developed by IBM, Qiskit has grown into a thriving ecosystem with over 6 million installations and a wide range of tools and plugins. It supports a flexible circuit model and a retargetable transpiler, enabling the representation and optimization of circuits at various abstraction levels. Qiskit's architecture includes circuits, pass managers, and primitives, which form the core components of the software. It allows for end-to-end workflows, such as solving problems in condensed matter physics on quantum computers, demonstrating capabilities like circuit synthesis, optimization, and quantum-classical integration. Qiskit's design philosophy emphasizes modularity, performance, portability, and interoperability across abstraction levels. It supports dynamic circuits, which enable real-time classical computation and error mitigation. The software also includes integrated visualizations, a tensor ordering convention, and a range of computational primitives for sampling and estimating observable expectation values. Qiskit's ecosystem includes a variety of tools and plugins that extend its functionality for different tasks. The software is designed to be scalable and efficient, with a focus on performance and ease of use. The release of Qiskit 1.0 marks a significant milestone, indicating its maturity and stability. Qiskit's architecture and capabilities make it a powerful tool for quantum computing research and development.