Awk

Show ASCII table
BEGIN { for (i=0; i<16; i++) { for (j=32+i; j<128; j+=16) { if (j == 32) { x = "SPC" } else if (j == 127) { x = "DEL" } else { x = sprintf("%c",j) } printf("%3d: %-5s",j,x) }      print "" } }
 * 1) Usage: awk -f showascii

Tally up a column of figures
case "$1" in [1-9]*) colnum="$1"; shift;;  *) echo "Usage: `basename $0` colnum [files]" 1>&2; exit 1;; esac awk '{sum += $col} END {print sum}' col=$colnum OFMT='%.2f' ${1+"$@"}
 * 1) ! /bin/sh

Use awk to list the thirty most-common words in a text file
{  nbytes += length($0) + 2 # +2 for CR/LF nfields += NF    $0 = tolower($0) for (i=1; i<=NF; i++) { arr[$i]++ } } END { show = (show == "") ? 30 : show width1 = length(show) PROCINFO["sorted_in"] = "@val_num_desc" for (i in arr) { if (width2 == 0) { width2 = length(arr[i]) } if (n++ >= show) { break } printf("%*d %*d %s\n",width1,n,width2,arr[i],i) }    printf("input: %d records, %d bytes, %d words of which %d are unique\n",NR,nbytes,nfields,length(arr)) exit(0) }
 * 1) Usage: awk -f wordfreq textfile.txt

Print lines with a unique first field
$ awk '!x[$1]++' ana5.txt abby baby abeam ameba abed bade bead abel able bale bela elba abet bate beat beta abets baste beast beats betas abetter beretta abhorred harbored abhorring harboring abhors hasbro abides biased able abel bale bela elba abler blare ablest bleats stable tables aboard abroad baroda abode adobe abridge brigade abridges brigades abroad aboard baroda abuse beaus abut batu tabu abuts tubas accouterments accoutrements accoutrements accouterments accrual caracul

Print a count of words by ending character
$ awk 'length > 1{++a[substr(tolower($0), length)]}END{for (k in a) print a[k], k}' /usr/share/dict/words | sort -n 1 j 2 á 2 q 29 é 45 v 132 z 159 u 172 b 195 x 196 f 254 w 479 p 492 i 760 o 797 c 816 k 957 m 1033 h 1753 a 2103 l 4304 r 4465 t 4513 n 5631 y 7090 g 7412 e 8064 d 50493 s