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awk, aka Aho, Weinberger, Kernighan, is a programming language created in 1977 by Alfred Aho and Peter J. Weinberger and Brian Kernighan.

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AWK is a programming language designed for text processing and typically used as a data extraction and reporting tool. It is a standard feature of most Unix-like operating systems. The AWK language is a data-driven scripting language consisting of a set of actions to be taken against streams of textual data – either run directly on files or used as part of a pipeline – for purposes of extracting or transforming text, such as producing formatted reports. Read more on Wikipedia...

awk website
awk Wikipedia page
awk docs
There are at least 2,552 awk repos on GitHub
awk first developed in Bell Labs
file extensions for awk include awk, auk, gawk, mawk and nawk
The Google BigQuery Public Dataset GitHub snapshot shows 14k users using awk in 21k repos on GitHub
There are 1,929 members in the awk subreddit
There are 14 Project Euler users using awk
Explore awk snippets on Rosetta Code
awk on HOPL
awk ranks #37 in the TIOBE Index
awk Ubuntu package
Pygments supports syntax highlighting for awk
GitHub supports syntax highlighting for awk
awk appears in the Quine Relay project
Indeed.com has 7 matches for "awk engineer".
See also: (14 related languages)C, SNOBOL, Bourne shell, Tcl, AMPL, Perl, Lua, Regular Expressions, Unix, sed, FreeBSD, Solaris, Java, ISBN

Example from Riju:

BEGIN { print "Hello, world!" }

Example from hello-world:

# awk -f awk.awk
BEGIN { print "Hello World" }

Example from the Hello World Collection:

# Hello world in AWK

BEGIN {
  print "Hello World!"
}

Example from Linguist:

#!/bin/awk -f

BEGIN {
  # It is not possible to define output file names here because
  # FILENAME is not define in the BEGIN section
  n = "";
  printf "Generating data files ...";
  network_max_bandwidth_in_byte = 10000000;
  network_max_packet_per_second = 1000000;
  last3 = 0;
  last4 = 0;
  last5 = 0;
  last6 = 0;
}
{
  if ($1 ~ /Average/)
    { # Skip the Average values
      n = "";
      next;
    }

  if ($2 ~ /all/)
    { # This is the cpu info
      print $3 > FILENAME".cpu.user.dat";
#	  print $4 > FILENAME".cpu.nice.dat";
      print $5 > FILENAME".cpu.system.dat";
#     print $6 > FILENAME".cpu.iowait.dat";
      print $7 > FILENAME".cpu.idle.dat";
      print 100-$7 > FILENAME".cpu.busy.dat";
    }
  if ($2 ~ /eth0/)
    { # This is the eth0 network info
      if ($3 > network_max_packet_per_second)
	print last3 > FILENAME".net.rxpck.dat"; # Total number of packets received per second.
      else
	{
	  last3 = $3;
	  print $3 > FILENAME".net.rxpck.dat"; # Total number of packets received per second.
	}
      if ($4 > network_max_packet_per_second)
	print last4 > FILENAME".net.txpck.dat"; # Total number of packets transmitted per second.
      else
	{
	  last4 = $4;
	  print $4 > FILENAME".net.txpck.dat"; # Total number of packets transmitted per second.
	}
      if ($5 > network_max_bandwidth_in_byte)
	print last5 > FILENAME".net.rxbyt.dat"; # Total number of bytes received per second.
      else
	{
	  last5 = $5;
	  print $5 > FILENAME".net.rxbyt.dat"; # Total number of bytes received per second.
	}
      if ($6 > network_max_bandwidth_in_byte)
	print last6 > FILENAME".net.txbyt.dat"; # Total number of bytes transmitted per second.
      else
	{
	  last6 = $6;
	  print $6 > FILENAME".net.txbyt.dat"; # Total number of bytes transmitted per second.
	}
#     print $7 > FILENAME".net.rxcmp.dat"; # Number of compressed packets received per second (for cslip etc.).
#     print $8 > FILENAME".net.txcmp.dat"; # Number of compressed packets transmitted per second.
#     print $9 > FILENAME".net.rxmcst.dat"; # Number of multicast packets received per second.
    }

  # Detect which is the next info to be parsed
  if ($2 ~ /proc|cswch|tps|kbmemfree|totsck/)
    {
      n = $2;
    }

  # Only get lines with numbers (real data !)
  if ($2 ~ /[0-9]/)
    {
      if (n == "proc/s")
	{ # This is the proc/s info
	  print $2 > FILENAME".proc.dat";
#	  n = "";
	}
      if (n == "cswch/s")
	{ # This is the context switches per second info
	  print $2 > FILENAME".ctxsw.dat";
#	  n = "";
	}
      if (n == "tps")
	{ # This is the disk info
	  print $2 > FILENAME".disk.tps.dat"; # total transfers per second
	  print $3 > FILENAME".disk.rtps.dat"; # read requests per second
	  print $4 > FILENAME".disk.wtps.dat"; # write requests per second
	  print $5 > FILENAME".disk.brdps.dat"; # block reads per second
	  print $6 > FILENAME".disk.bwrps.dat"; # block writes per second
#	  n = "";
	}
      if (n == "kbmemfree")
	{ # This is the mem info
	  print $2 > FILENAME".mem.kbmemfree.dat"; # Amount of free memory available in kilobytes.
	  print $3 > FILENAME".mem.kbmemused.dat"; # Amount of used memory in kilobytes. This does not take into account memory used by the kernel itself.
	  print $4 > FILENAME".mem.memused.dat"; # Percentage of used memory.
#         It appears the kbmemshrd has been removed from the sysstat output - ntolia
#	  print $X > FILENAME".mem.kbmemshrd.dat"; # Amount of memory shared by the system in kilobytes.  Always zero with 2.4 kernels.
#	  print $5 > FILENAME".mem.kbbuffers.dat"; # Amount of memory used as buffers by the kernel in kilobytes.
	  print $6 > FILENAME".mem.kbcached.dat"; # Amount of memory used to cache data by the kernel in kilobytes.
#	  print $7 > FILENAME".mem.kbswpfree.dat"; # Amount of free swap space in kilobytes.
#	  print $8 > FILENAME".mem.kbswpused.dat"; # Amount of used swap space in kilobytes.
	  print $9 > FILENAME".mem.swpused.dat"; # Percentage of used swap space.
#	  n = "";
 	}
      if (n == "totsck")
	{ # This is the socket info
	  print $2 > FILENAME".sock.totsck.dat"; # Total number of used sockets.
	  print $3 > FILENAME".sock.tcpsck.dat"; # Number of TCP sockets currently in use.
#	  print $4 > FILENAME".sock.udpsck.dat"; # Number of UDP sockets currently in use.
#	  print $5 > FILENAME".sock.rawsck.dat"; # Number of RAW sockets currently in use.
#	  print $6 > FILENAME".sock.ip-frag.dat"; # Number of IP fragments currently in use.
#	  n = "";
 	}
    }
}
END {
  print " '" FILENAME "' done.";
}

Example from Wikipedia:

BEGIN {
    pattern = ARGV[1]
    for (i = 1; i < ARGC; i++) # remove first argument
        ARGV[i] = ARGV[i + 1]
    ARGC--
    if (ARGC == 1) { # the pattern was the only thing, so force read from standard input (used by book)
        ARGC = 2
        ARGV[1] = "-"
    }
}
$0 ~ pattern { print FILENAME ":" $0 }

Feature	Supported	Token	Example
Integers	✓		# [0-9]+
Floats	✓		# [0-9][0-9]*\.[0-9]+([eE][0-9]+)?[fd]?
Hexadecimals	✓		# 0x[0-9a-fA-F]+
Strings	✓	"	"Hello world"
Print() Debugging	✓	print
Line Comments	✓	#	# A comment
Comments	✓
Semantic Indentation	X

awk - Programming language

Language features