audio recording

A preamp boosts the input signal, from a mic or instrument, to a usable level. Most audio interfaces include a preamp.

A device that gets audio in and out of your computer. All computers and laptops will have a basic built in sound card that will handle inputs (mic/line in) and outputs (to speakers/headphones). For professional audio you will need an additional soundcard/interface. These comes in various forms, USB, Firewire and PCI devices.

Understanding recording hardware

FFADO stands for Free FireWire Audio Drivers. This is an open source device driver backend for JACK. If you want to use a firewire interface, check out the FFADO website to see which devices are supported.

Pulse audio is a sound server that uses ALSA as it's backend. It is more geared towards general desktop audio. While it is useful for these purposes, pulse audio isn't used for any audio production software.

The Jack Audio Connection Kit is a professional sound server for low latency audio and MIDI connections. When running JACK you can interconnect audio and MIDI ports between any JACK aware programs. It is a very flexible system that can allow for very modular set ups, but is also used to manage connections within various pieces of software, eg. Ardour and Qtractor.

The Advanced Linux Sound Architecture is a audio framework, which is part of the Linux kernel. Both JACK and Pulse Audio use ALSA as their backend. Unless you are using a firewire device (see FFADO), it is ALSA that you will be looking at to see if your audio interface is supported. ALSA also has MIDI device support. A list of ALSA supported audio interfaces can be found on the ALSA website.