What it's for
Port 1080 is the conventional default port for a SOCKS proxy — a general-purpose protocol for routing arbitrary network traffic through an intermediary server, without the proxy needing to understand the specific application protocol being tunneled (unlike an HTTP proxy, which specifically understands HTTP). This makes SOCKS proxies useful for tunneling all sorts of traffic — not just web browsing — through a single relay point.
Protocol basics
SOCKS operates over TCP and works at a lower level than application-specific proxies: the client tells the SOCKS server the destination address and port it wants to reach, and the SOCKS server simply relays bytes back and forth without inspecting or understanding the actual application data. A common real-world pattern is ssh -D 1080 user@host, which spins up a local SOCKS proxy tunneled through an SSH connection — a quick way to route browser or application traffic through a remote server without setting up a full VPN.