Deep web (or invisible web) is a part of the web that is not indexed by search engines. Not to be confused with dark web (or dark net), deep web has “non-offensive” indexable content.
The reasons why this content is not indexed are various: pages requiring payment, bank accounts, emails, content, content reserved for subscribers (example of a paid press article), structure too complex, etc.
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We therefore access the deep web every day, only we don't realise it. Transattentionnal cyberspace encompasses that part of the web: rather than staying on the surface web, which is the most known part of the web with all the indexed elements, we think with transattentionality to go beyond what we can see and what we know. This notion is therefore omnipresent in our daily lives, and makes us use the notion of transattention unconsciously. But transattentionnal cyberspace can also be used intentionally to access darker parts of the internet, such as the dark net.
Maxime Jean & Alexis Mellin