Open source software (OSS) is software released under an open source license that allows for modification and redistribution. Common open source licenses include the Apache License, GPL, and MIT license. There are many misconceptions about open source such as it being low quality or only for hobbyists. Companies can monetize open source in various ways such as support contracts, selling related products, cloud services, or foundations. For developers, open source provides learning opportunities through collaboration and the potential to make money by developing plugins, providing support, or working for an open source company. Many widely-used technologies like Linux, Android, and PHP started as open source projects.