The following table converts the unix timestamp 956100030 to various other RFC formats:
| < 956100000 — 956100029 | 956100031 — 956150000 > | 
| Standard name | Equivalent | 
|---|---|
| Unix Timestamp: | |
| ANSIC: | in ANSIC format | 
| UnixDate: | in Unix Date format | 
| RubyDate: | in Ruby Date format | 
| RFC822: | in RFC 822 | 
| RFC822Z: | in RFC822Z format | 
| RFC850: | in RFC 850 format | 
| RFC1123: | in RFC 1123 format | 
| RFC1123Z: | in RFC 1123Z format | 
| RFC3339: | in RFC 3339 format | 
| RFC3339Nano: | in RFC 3339 nano format | 
| RFC2822: | in RFC 2822 format | 
| < 956100000 < 956100029 | 956100031 — 956150000 > | 
It's the number of seconds since the Unix Epoch. The Unix Epoch starts January 1st, 1970 at UTC, and skips leap seconds. The Unix Epoch is based on a UTC starting point, so does not change in different timezones. Read more on wikipedia.
In early 2038 the Unix Time Stamp, if uses 32-bit signed integer, will overflow. This is really bad. Older systems will need to upgrade their timestamp storage to cope to avoid failure. Read more on wikipedia.