Explain a Command

A quick way to see what commands and their options do before running them.

Generate a random 16-char password

strings /dev/urandom | grep -o '[[:alnum:]]' | head -n 16 | tr -d '\n'

strings	strings(1) print the sequences of printable characters in files
/dev/urandom
\|	⇓
grep	grep(1) print lines that match patterns
-o	-o, --only-matching Print only the matched (non-empty) parts of a matching line, with each such part on a separate output line.
'[[:alnum:]]'
\|	⇓
head	head(1) output the first part of files
-n 16	-n, --lines=[-]NUM print the first NUM lines instead of the first 10; with the leading '-', print all but the last NUM lines of each file
\|	⇓
tr	tr(1) translate or delete characters
-d	-d, --delete delete characters in ARRAY1, do not translate
'\n'

Delete files extracted from a tarball
tar -tf file.tar.gz | xargs rm -r

Print the largest files or folders in the current dir
du -s * | sort -n | tail

From our blog:

Want to build something like this? Have a look at ManKier's API.

For another take on explaining commands, check out explainshell.com.