Semiconductor quantum computation has been a rapidly growing field in the past years thanks to a global investigation on realizing fault-tolerant implementations. Experiments on physical devices are indeed yielding very good results in terms of gate fidelities and coherence times. Quantum dots are one of the most explored possibilities for semiconductor quantum implementation, thanks to their flexibility and technological readiness for such application. Yet, this is not the only option available for semiconductors: different technologies, namely dopants and optically addressable quantum defects, are accessible, but gate-defined quantum dots offer enough advantages over those alternatives to justify the extensive research carried out on them.