Annotating texts has been done for centuries, but it is a challenge when it comes to digital content. However, the potential for capturing and sharing annotations in a digital environment makes them more valuable. Annotation was actually a critical component of the World Wide Web’s foundation, and it was even a feature in the first widely distributed web browser, Mosaic. Several start-ups have attempted to develop annotation services, but they have faced challenges and have not succeeded. However, there are currently many web annotation services available, and the iAnnotate meeting in San Francisco brought together technologists interested in digital annotation to discuss its future. There are challenges to developing shared annotation systems, such as locating a reference point and issues with copyright and privacy. Despite these challenges, the potential that annotation services have in advancing understanding of science is immense, and the scholarly publishing community should pay more attention to its development.
https://scholarlykitchen.sspnet.org/2013/04/30/iannotate-whatever-happened-to-the-web-as-an-annotation-system/