# display content of x.txt
% more x.txt
apple:12
banana:5
peach:10
peach:10
peach:10
pineapple:2
orange:12

# separate each line of x.txt into field0, field1, ... using delimiter ':' 
# sort lines in ascending order based on field1 numerical sort
#  and output the sorted lines after removal of duplicate lines
% sort -t: +1n -u x.txt
pineapple:2
banana:5
peach:10
apple:12

# for each line of x.txt,
#  separate fields into $1, $2, ... using delimiter ':'
#  if the line contains the pattern /p/, 
#    perform the action
#      print $1, $2 according to the format specifier
#          $1 as a string within 10 columns (left justified)
#          $2 as an integer within 3 columns (right justified)
#          followed by a end-of-line 
% awk -F: '/p/ {printf "%-10s %3i\n",$1,$2}' x.txt
apple       12
peach       10
peach       10
peach       10
pineapple    2

# the pattern searches for 'l' or 'g' in the line
% awk -F: '/l|g/ {printf "%-10s %3i\n",$1,$2}' x.txt
apple       12
pineapple    2
orange      12

# display all lines of x.txt after removing duplicate lines
% uniq x.txt
apple:12
banana:5
peach:10
pineapple:2
orange:12

# display only the lines of x.txt that have duplicates
% uniq -d x.txt
peach:10

# display only the lines of x.txt that do not have duplicates
% uniq -u x.txt
apple:12
banana:5
pineapple:2
orange:12

# display content of y.txt
% more y.txt
apple:12
banana:5
pear:10
pineapple:2
orange:12

# translate (replace) ':' by ' ' in y.txt and save the output in z.txt
% tr : \  < y.txt > z.txt

# display content of z.txt
% more z.txt
apple 12
banana 5
pear 10
pineapple 2
orange 12

# translate 'a' by '@',  'g' by 'x'  in x.txt and display the output
% tr ag @x < x.txt
@pple:12
b@n@n@:5
pe@ch:10
pe@ch:10
pe@ch:10
pine@pple:2
or@nxe:12

# display number of lines, words, and bytes in file z.txt
% wc z.txt
      5      10      48 z.txt

# display number of lines in file z.txt
% wc -l z.txt
      5 z.txt

# display number of words in file z.txt
% wc -w z.txt
     10 z.txt

# display number of bytes in file z.txt
% wc -c z.txt
     48 z.txt

# stream edit file x.txt and delete lines 3-8 and display the output
% sed 3,6d < x.txt
apple:12
banana:5
orange:12

# also, substitute string "an" by "tin"
#  note the substitution occurs only for the first occurrence in each line
% sed 3,6d < x.txt | sed -e 's/an/tin/'
apple:12
btinana:5
ortinge:12

#  the substitution occurs for all occurrences in each line
% sed 3,6d < x.txt | sed -e 's/an/tin/g'
apple:12
btintina:5
ortinge:12