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4 min read · Jan 31, 2022
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In computer science, the epoch time, also known as Unix time, is considered the number of seconds since 1 January 1970. In other words, it is the number of seconds counted since that day.
The epoch time is the same for every country regardless of where you stay in the globe. The epoch time is measured in seconds.
The epoch refers to the instance of time. Thus, epoch time refers to the number of seconds from the zero point or epoch time.
Epoch time is purely used for efficiency reasons as it takes less space to represent a single number in seconds rather than storing in words like year, month, hour etc.
To measure height, weight or anything, you need an initial value. For example, you need to have an initial value to measure the height. The initial value to measure height is 0cm or 0m. you cant start to measure the height from negative values. 0 is considered as the default standard when it comes to measuring weight and height. The same theory applies to computers; The computer needs to know where to begin tracking the time. The epoch time is considered as one the most popular convention for computers to track time. The epoch starts at 00:00:00 Thursday 01 January 1970, UTC. Epoch time is completely measured in seconds. It is also known as the number of seconds since epoch 0
A computer requires an initial value to add some seconds on top of it. Adding some value to an unspecified point in time wouldn’t make any sense. To give an initial zero point, the epoch time has been added.
Computers can only interrupt binary codes, also known as 1s and 0s. Therefore, scientists came up with a solution to help computers understand date by simply providing it in seconds(numeric values). These seconds were calculated by simply picking a reference point and counting the number of seconds since that reference point, known as epoch time.
During 1970 and 1971, the Unix Systems were developed, and around 1971 they released the initial or the first internal manual.
Dennis Ritchie and Ken Thompson were the people to develop the Unix Systems, and they decided to set the first epoch on 01/01/1971.
Around 1971 the Unix development team set the first epoch on 01/01/1971. The Unix development team wanted to decide a recent epoch time and date as there zero point since the earliest versions of Unix 32 bit systems were only able to represent in a short time span with less than 850 days. This issue occurred because the Unix 32 bit systems measured time in 1/60th seconds intervals.
Later on, Unix System started to measure the time in 1-second intervals; thus, the time span has been able to increase from 829 days to 136 years. Due to this fact, the epoch was no longer needed to be one of the recent.
After a while, the epoch was once again changed to 01/01/1970. Which was the beginning of the decade, and this change was done for many convenient reasons
You can view your current Epoch time and do the necessary calculations here.
As of now, the epoch time is a very big number since many computers operate on 32 bits. Epoch time is almost going to pass the number that 32 bit systems can understand. It is expected that around January 19th 2038, the epoch time will surpass the maximum number that a 32-bit system can understand. Any software using 32-bit timestamps needs to be updated to a new convention to solve this. One way to do this is by migrating the 32-bit system into a 64 bit one. If the necessary updation is not done before the time exceeds the limited number, it will be falsely interpreted as FRIDAY 13 DEC 1901 UTC, and this problem is known as the Year 2038 problem in computer science.
The computer requires an initial value or the base so that the computer can add seconds on top of it. If the computer adds seconds on top of an unspecified value, it doesn’t make sense. Therefore, epoch time, also known as zero time, is considered the base. January 1st 1970, is considered as the epoch time by Unix systems and Dennis Ritchie and Ken Thompson made this decision.
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