Show lines that are present on file 1 but are not present in file 2 (line order does not matter)

Remove anything but letters (a-z) from strings (use with pipe) ex: cat text.txt |letters

remove special chars from strings (use with pipe)

display only numbers in strings (use with pipe)

ex:

$ cat file.txt
A331
this is a numeber: 44
nothing
more nothing @

$ cat file.txt|numbers
331
44

lower everything (pipe)

upper everything (pipe)

read two files and remove from the first file any content present in the second file (non destructive, it just print the result to stdout)

take text as input and prints out just found ip addressess and/or ports along with ips:

take a file from -l or stdin and remove lines based on a subset of rules (fuzzy match, regex match, string match, char count and randomness)