Unix Timestamp: Seconds or Milliseconds?

The example project for the timestamp project seems to count the number of seconds since January 1, 1970 (took me some time to figure out why my code throws a different date from the example). I’m confused here. Shouldn’t it be the number of milliseconds?

EDIT Okay I looked at other campers’ timestamp projects and saw that they are counting seconds. I did a quick look up and found that I should use seconds.

@moderators can you close this post? Thanks.