The internet is commonly divided into three layers:
- Surface Web (4-5% of the internet): Everything indexed by search engines like Google, Bing, and DuckDuckGo. Websites you find through a normal search - news sites, social media, Wikipedia, online stores. Anyone can access these pages without special tools.
- Deep Web (90-95% of the internet): Content that exists online but is NOT indexed by search engines. This includes your email inbox, online banking, private databases, medical records, academic journals behind paywalls, corporate intranets, and password-protected content. You access the deep web every day without realizing it.
- Dark Web (less than 0.1% of the internet): A small subset of the deep web that requires special software to access - primarily the Tor Browser. Dark web sites use .onion addresses and are intentionally hidden. This is where anonymous communication, censorship-resistant publishing, and privacy tools exist.
The key insight: the deep web is huge and mostly mundane (your email is deep web). The dark web is tiny and requires Tor.