Deep web sites can be accessed by a direct URL or IP address, but may require entering a password or other security information to access actual content.[7][8] Uses of deep web sites include web mail, online banking, cloud storage, restricted-access social-media pages and profiles, and web forums that require registration for viewing content. It also includes paywalled services such as video on demand and some online magazines and newspapers.
^Devine, Jane; Egger-Sider, Francine (August 2021). "Beyond google: the invisible web in the academic library". The Journal of Academic Librarianship. 30 (4): 265–269. doi:10.1016/j.acalib.2004.04.010.
^Raghavan, Sriram; Garcia-Molina, Hector (September 11–14, 2001). "Crawling the Hidden Web". 27th International Conference on Very Large Data Bases.
^Madhavan, J., Ko, D., Kot, Ł., Ganapathy, V., Rasmussen, A., & Halevy, A. (2008). Google's deep web crawl. Proceedings of the VLDB Endowment, 1(2), 1241–52.