TOR is a network that enables anonymous communication over the internet by routing the traffic through a series of relays or nodes. TOR alters the data content during transit by encrypting it and the destination information over multiple layers, using a technique called onion routing. Each layer of encryption can only be decrypted by a specific relay in the network, which reveals the next destination. This way, no single relay knows the complete path or the content of the data, making it difficult to trace or monitor the communication. Reference:= Cisco Cybersecurity Operations Fundamentals, Module 2: Security Monitoring, Lesson 2.1: The Network as a Sensor, Topic 2.1.3: Network Data Exfiltration Techniques