apaste: paste the input files lines together
the result is put onto the standard out

parameters:
-s[ep] {s}: specify separator character ('|' by default)
other parameters are interpreted as input file names

Exmaples:
apaste one.txt two.txt

one.txt: apple\nplum
two.txt: blueberry\ngrape
result:
apple|blueberry
plum|grape