2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49819We review the quantization of open string in NS-NS background and demonstrate that its endpoint becomes noncommutative. The same approach allows us to determine the noncommutativity that arises for a charged open string in background gauge fields. While NS-NS background is relevant for ``worldvolume'' noncommutativity, a simple argument suggests that RR background is likely to be relevant for ``spacetime'' noncommutativity.11 pages. Talk presented at the Anttila winter school and workshop on ``String theory and Gauge theory'' (Anttila, Sweden, Feb 1999), and the International Workshop ``Supersymmetries and Quantum Symmetries'' (Dubna, Russia, July 1999), to appear in the proceedingsHigh Energy Physics - Theorytext