explainshell.com - cat Evidencias%2FBulk_PC-20170427_%2Fjson.txt %7C egrep -Eo %22%5Ba-zA-Z0-9%5D%2B%40%5Ba-zA-Z0-9%5D%2B%5B.%5D%5Ba-zA-Z0-9%5D%22 %7C sort %7C uniq

Evidencias%2FBulk_PC-20170427_%2Fjson.txt %7C egrep -Eo %22%5Ba-zA-Z0-9%5D%2B%40%5Ba-zA-Z0-9%5D%2B%5B.%5D%5Ba-zA-Z0-9%5D%22 %7C sort %7C uniq

concatenate files and print on the standard output

Concatenate FILE(s), or standard input, to standard output.

With no FILE, or when FILE is -, read standard input.

-E, --show-ends
       display $ at end of each line

source manpages: cat