Searching the Internet usually starts with Google. Everyone knows Google, Google finds everything. Really everything?
Search engines are programs that search and index the World Wide Web. To do this, a crawler (also called a "spider" or "robot") is sent through the Internet. Its task is to follow the links on each page and to remember new or changed pages. These results are then transferred to the search engine index. If a user now starts a search query, the search result is compiled from the index.
Scientific institutes, professional associations and research societies from various disciplines offer specialized search engines and web directories. These search services offer resources with a high quality standard and are particularly recommended for searching for subject-specific information and scientifically profounded literature on the Internet.
On our library homepage you will also find information on freely accessible "virtual libraries" under the heading Research > Research portals. These specific portals also contain resources with higher quality standards.
Deep Web: Many contents of the Internet cannot be found with the help of (general) search engines. The 'invisible web', as it is also called, is largely composed of: