A darknet is an overlay network within the Internet that can only be accessed with specific software, configurations, or authorization (e.g. TOR, Freenet, I2P or ZeroNet) intended to defend digital rights by providing security, anonymity, and censorship resistance. Though it is used for legitimate reasons, it has been heavily used by criminals and the term Darknet nowadays is generally associated with websites (also called onion sites) that are specifically used for criminal purposes.

NOTE: Darkweb term does not exist (it is either Darknet or Deep web)