A timestamp is a sequence of characters or encoded information identifying when a certain event occurred, usually giving date and time of day, sometimes accurate to a small fraction of a second. Timestamps are widely used in computer systems as time references for files and events. Most computer systems record timestamps in the format used by the Date Time Group (DTG) system. Many implementations use Unix time, which encodes time as the number of seconds since the start of the Unix epoch.
In many cases, a timestamp is sufficient to uniquely identify a particular event or file. However, in other cases, a more complex identifier, such as a sequence number, may be required.
How do you read a timestamp?
A timestamp is a sequence of characters or encoded information identifying when a certain event occurred, usually giving date and time of day, sometimes accurate to a small fraction of a second. Timestamps are widely used in computer systems as time references.
There are a few different ways to read a timestamp, depending on the format it is in. For example, a timestamp in Unix time format is the number of seconds since January 1, 1970. To read this type of timestamp, you would need to convert it to a more readable format, such as the number of days, hours, minutes, and seconds since that date.
Another common format is the ISO 8601 standard, which uses a combination of numbers and letters to represent dates and times. For example, the timestamp "2015-03-25T12:00:00Z" would be read as "March 25, 2015 at 12:00:00 GMT." To read this type of timestamp, you would need to first identify the different parts of the timestamp (year, month, day, hour, minute, second, time zone) and then convert each part to a more readable format.
yet another format is the RFC 3339 standard, which is similar to ISO 8601 but uses a different time zone identifier. For example, the timestamp "2015-03-25T12:00:00-07:00" would be read as "March 25, 2015 at 12:00:00 PDT
How long is a timestamp?
A timestamp is a sequence of characters or encoded information identifying when a certain event occurred, usually giving date and time of day, sometimes accurate to a small fraction of a second.
Most timestamps are represented in local time. A timestamp in GMT is sometimes denoted with a suffixed letter Z, for "zero meridian", "zulu", or "UTC+0". The RFC3339 standard format for timestamps is:
YYYY-MM-DDTHH:MM:SS.sssZ
where:
YYYY: four-digit year
MM: two-digit month (01=January, etc.)
DD: two-digit day of month (01 through 31)
HH: two digits of hour (00 through 23) (AM/PM hours are 12-hour clock)
MM: two digits of minute (00 through 59)
SS: two digits of second (00 through 59)
sss: three digits of subsecond (000 through 999)
The timezone is always zero UTC offset, as denoted by the suffix "Z".
RFC3339 also defines a restricted format, where the subsecond component is optional:
YYYY-MM-DDTHH:MM:SSZ
A timestamp in Unix time, also called Epoch time, is simply an integer representing the number of seconds since January 1st, 1970 at UTC. Negative numbers
How many digits is a timestamp?
A timestamp is a sequence of characters or encoded information identifying when a certain event occurred, usually giving date and time of day, sometimes accurate to a small fraction of a second. A timestamp is the time at which an event is recorded by a computer, not the time when the event occurs.
There are various ways to measure time, each with different accuracy and resolution. For example, Unix and POSIX measure time as the number of seconds since the Unix epoch, which began at 00:00:00 Coordinated Universal Time (UTC), Thursday, 1 January 1970. This timestamp is an absolute reference; subsequent timestamps are measured as offsets from this epoch.
Other systems, such as Microsoft Windows, measure time as the number of 100-nanosecond intervals since 00:00:00 UTC, 1 January 1601. This timestamp is also an absolute reference; subsequent timestamps are measured as offsets from this epoch.
The number of digits in a timestamp depends on the system and the resolution at which time is measured. For example, a timestamp measured in seconds since the Unix epoch can be represented with at most 10 digits (seconds are measured in tens), and a timestamp measured in 100-nanosecond intervals can be represented with at most 29 digits (100-nanosecond intervals are measured in quadrillions).