What is deep/dark web ?
The Internet: This is the easy one. It’s the common Internet everyone uses to read news, visit Facebook, and shop. Just consider this the “regular” Internet.
The Deep Web: The deep web is a subset of the Internet that is not indexed by the major search engines. This means that you have to visit those places directly instead of being able to search for them.
For Example,You upload your personal DATA on Google Drive or Drop box,so that data is only accessible by you no one can view or search about that data,so that's call a Deep Web,So the Deep Web is the long tail of what’s left out.
The Dark Web: The Dark Web (also called Darknet) is a subset of the Deep Web that is not only not indexed, but that also requires something special to be able to access it, e.g., specific proxying software or authentication to gain access. The Dark Web often sits on top of additional sub-networks, such as Tor, I2P, and Freenet, and is often associated with criminal activity of various degrees, including buying and selling drugs, pornography, gambling, etc.
"Summary"
The Internet is where it’s easy to find things online because what you’re searching for is all in search engines.
The Deep Web is the part of the Internet that isn’t necessarily malicious, but is simply too large and/or obscure to be indexed due to the limitations of crawling and indexing software (like Google/Bing/Baidu).
The Dark Web is the part of the non-indexed part of the Internet (the Deep Web) that is used by those who are purposely trying to control access because they have a strong desire for privacy, or because what they’re doing is illegal.
"Notes"
The Wikipedia article on the Deep Web.
The Wikipedia article on the Dark Web.
After Read this post you simply know all term,But I defiantly know There is one question traveling in your mind "How Can I Access Dark Web ?" So Click on that and explore it.

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