In addition to Wikipedia, researchers examined users’ motivations for contributing to other online communities. Nov and colleagues  found a positive relationship between the motivation to build a reputation in the community and the number of tags contributed in Flickr. Similarly, in an earlier study examining an online network of legal professionals, Wasko and Faraj  found a significant positive effect on the motivation to build a reputation from the quality and volume of knowledge contributed. Hars and Ou  examined the motivations of contributors to free and open source software (FOSS) projects. They identified two categories of motivations: internal and external. Internal motivations included factors related to self-determination, as well as altruism and community identification. The external motivation category included factors related to future rewards (e.g., enhanced status and self-efficacy) and personal needs for open source software functionalities. As motivations to participate in FOSS projects, Lakhani and Wolf  identified self-identification with a community and a sense of obligation to contribute, along with the motivations of a sense of enjoyment and receiving rewards.