proc asound devices 0.2

$cat /proc/asound/devices
  2:        : timer
  3:        : sequencer
  4: [ 0- 2]: digital audio capture
  5: [ 0- 1]: digital audio playback
  6: [ 0- 1]: digital audio capture
  7: [ 0- 0]: digital audio playback
  8: [ 0- 0]: digital audio capture
  9: [ 0- 0]: hardware dependent
 10: [ 0]   : control

        Lists the ALSA native device mappings.
A music  sequencer is  a musical application  or a device  designed to
play  back musical  notation. The  original kind  of sequencer  is now
known  as a step  sequencer to  distinguish it  from the  modern kind,
which records a musician playing notes.

GNUsound - A sound editor  for Linux/x86. It supports multiple tracks,
multiple  outputs, and  8, 16,  or 24/32  bit samples.  It can  read a
number of audio formats through libaudiofile, and saves them as WAV.
GNU sound

Digital audio uses pulse-code modulation and digital signals for sound
reproduction.   This  includes  analog-to-digital   conversion  (ADC),
digital-to-analog  conversion  (DAC),  storage, and  transmission.  In
effect,  the system  commonly  referred to  as  digital is  in fact  a
discrete-time,   discrete-level  analog   of  a   previous  electrical
analog. While modern systems can be quite subtle in their methods, the
primary  usefulness of  a  digital  system is  the  ability to  store,
retrieve and transmit signals without any loss of quality.
Intel's  use  of  the  phrase  audio codec  refers  to  signals  being
encoded/decoded  to/from  analog  audio  from/to digital  audio,  thus
actually a combined audio AD/DA-converter. This should not be confused
with a  codec in  the sense  of converting from  one binary  format to
another,  such as  an audio  (MP3) or  video (Xvid)  codec in  a media

A timer is a specialized type of clock. A timer can be used to control
the  sequence of  an  event  or process.  Whereas  a stopwatch  counts
upwards from zero for measuring elapsed time, a timer counts down from
a  specified   time  interval,  like  an  hourglass.   Timers  can  be
mechanical, electromechanical,  electronic (quartz), or  even software
as  all  modern  computers  include  digital timers  of  one  kind  or
another. When  the set period  expires some timers simply  indicate so
(e.g.,  by  an  audible   signal),  while  others  operate  electrical
switches, such as a time switch, which cuts electrical power.