# Glossary

| Term | Translation |
|------|-------------|
| AX.25 | The underlying packet radio protocol, sometimes used as a generic term |
| AFSK | Audio Frequency Shift Keying. See [Modulation](beginners-guide.md#modulation) |
| BBS | Bulletin Board System - an email and message service hosted on a nearby mailbox |
| BSD | Berkely System Distribution - Linux's inspiration and predecessor, a commercial (now largely open source) family of Unix distributions | 
| bd | Baud - a unit of data - 1 character, used to explain the speed of a link as bauds per second |
| CLI | Command Line Interface - a text-first mode of interacting with the computer |
| FSK | Frequency Shift Keying. See [Modulation](beginners-guide.md#modulation) |
| IP | Internet Protocol |
| IL2P | Improved Layer 2 Protocol - a new protocol to replace AX.25 over the air |
| Kernel | The Linux Kernel is the core component of Linux, common to all distributions and the only atually part technically called Linux. It's the software at the very bottom of the pile, interacting with hardware and making stuff work |
| KISS | Keep it Simple Stupid - a serial protocol to communicate with modems |
| Linux | A family of computer operating systems, alternative to Windows |
| NET/ROM | A routing and discovery layer that makes connecting to nearby and distant stations easier |
| Node | A computer in the network. It can be a full featured system with applications hosted at home or at a nearby site, or it can be a simplified system that only passes messages on behalf others |
| Repo | Repository of applications for a Linux Distribution - see [Applications and Repositories](linux.md##applications-and-repositories) |
| PMS | Personal Message System - a reduced functionality BBS hosted on your home node |
| PSK | Phase Shift Keying. See [Modulation](beginners-guide.md#modulation) |
| QPSK | Quadrature Phase Shift Keying. PSK based on 4 different phase states. See [Modulation](beginners-guide.md#modulation) |
| TCP | Transmission Control Porotocol. A protocol for transmitting data over an IP Link |
| TNC | Terminal Node Controller - A modem with enhanced functionality. See [TNC](modems/index.md#what-is-a-tnc)
