An entry node is the server you connect to when you use the Tor network. Traffic through the Tor network is routed through 3 servers: An entry, middle, and exit node. This route is also called a circuit. The entry node sees your computer’s IP address, but it doesn’t see what website you’re connecting to (only the exit node will see that). This separation of information is what protects you when you use Tor Browser, no Tor node has full visibility into your traffic, so no single node can de-anonymize you.