The manual page and help for the nc.openbsd Linux command. The nc (or netcat) utility can be used for almost anything, including things related to TCP, UDP, or UNIX-domain sockets. It can open TCP connections, send UDP packets, listen on any TCP and UDP ports, perform port scanning, and manage both IPv4 and IPv6 networks. Unlike telnet, nc scripts nicely and sends error messages correctly to stderr instead of stdout like telnet does.

The manual page and help for the nc.traditional Linux command. netcat is a simple unix utility that reads and writes data over network connections using the TCP or UDP protocol. It is designed to be a reliable "backend" tool that can be used directly or easily controlled by other programs and scripts. At the same time, it is also a feature-rich network troubleshooting and discovery tool, as it can create almost any connection you might need and has many interesting built-in capabilities.

The manual page and help for the nc / ncat Linux command. Ncat is a network utility with functions that read and write data from the command line over networks. It is designed to be a reliable back-end device that provides instant network connectivity to other applications and users. Netcat can be used to debug and monitor network connections, search for open ports, transfer data, etc.