Yep, all Unix/Linux/BSD operating systems measure time in seconds from midnight UTC on 1 Jan 1970. Local, human-readable time and date is converted from that. I've seen screenshots of phone apps that said 11:59 PM, 31 Dec 1969, because Unix Time defaulted to -1 second. That usually happens when there's no data for time, it defaults to 0 or -1. And now you know more than you ever wanted to know about computer time.