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 id: l29u
 title: Time_and_computers
 tags: []
-created: Sunday, April 28, 2024 
+created: Sunday, April 28, 2024
 ---
+
 # Time_and_computers
 
+## Epochs and Unix Time
 
-## Related notes
+An epoch is a period of time identified by a starting point.
 
+The standard epoch for measuring against is known colloqially as "Unix Time":
+midnight on 1st January 1970. Unix time is the number of seconds that have
+elapsed since this point. This is the standard for Windows and most unix
+systems.
 
+For example midnight on 2nd January 1970 would be 86400 seconds since the epoch.
+The deduction is as follows:
+
+```
+60 * 60 * 24 = 86400
+```
+
+We are multiplpying the number of seconds in a minute by the number of minutes
+in an hour by the number of hours in a day.