They exist in case we ever make CONTACT
with an alien civilization.
The Big Bang Theory Season 9, Episode 10
If we run into any problems, I'll CONTACT you.
The Big Bang Theory Season 8, Episode 6
where the last puzzle gives the winner
Sheldon's CONTACT information.
The Big Bang Theory Season 9, Episode 8
Can I get his CONTACT info?
The Big Bang Theory Season 9, Episode 17
...to provide Amy with conversation
and casual physical CONTACT.
The Big Bang Theory Season 6, Episode 1